please help!!! i really need it

a) The drawing of all data points on a 2D plane is illustrated below.

b) The angle in between the five other points is 27

c) The matrix outer product for X is R = XXT.

d) The matrix outer product can also be calculated via R is (2,27)

The data matrix X is a 2-by-7 matrix, where each column represents a data point with two components. We can visualize each data point as a vector in a two-dimensional plane, where the horizontal axis represents the first component and the vertical axis represents the second component.

To draw all data points on a 2D plane, we can plot each column of X as a vector starting from the origin. Proper labeling of the two axes and providing important tick values will facilitate a precise graphical description of the data.

Next, we can use the inner product formula to calculate the angle between the first data point (2, 27) and the other five data points, respectively.

The inner product, also known as the dot product, is a way to measure the similarity between two vectors by multiplying their corresponding components and summing the products.

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Answer:

(1, 2) and (-1, -2). or. (±1, ±2)

Step-by-step explanation:

[tex]{ \sf{f(x) = \frac{4x}{ {x}^{2} + 1 } }} \\ [/tex]

- Simply, a critical number or critical point is gotten by differentiating the function.

From Quotient rule;

[tex]{ \sf{ {f}^{l}(x) = \frac{4( {x}^{2} + 1) - (2x)(4x)}{ {( {x}^{2} + 1)}^{2} } }} \\ \\ { \sf{f {}^{l}(x) = \frac{ {4x}^{2} + 4 - {8x}^{2} }{ {( {x}^{2} + 1) }^{2} } }} \\ \\ { \sf{f {}^{l}(x) = \frac{4(1 - {x}^{2}) }{ {( {x}^{2 } + 1) }^{2} } }}[/tex]

Then equate this derivative to zero;

[tex]{ \sf{0 = \frac{4(1 - {x}^{2} )}{ {( {x}^{2} + 1) }^{2} } }} \\ \\ { \sf{4(1 - {x}^{2} ) = 0}} \\ \\ { \sf{4 - {4x}^{2} = 0}} \\ \\ { \sf{4 {x}^{2} = 4}} \\ \\ { \sf{x = \sqrt{1} }} \\ \\ { \sf{ \underline{ \: x = \pm 1 \: }}}[/tex]

Substitute for x in f(x)

For x = 1

[tex]{ \sf{f(1) = \frac{4(1)}{ {(1)}^{2} + 1} = \frac{4}{2} = 2 }} \\ [/tex]

For x = -1

[tex]{ \sf{f( - 1) = \frac{4( - 1)}{ {( - 1)}^{2} + 1 } = \frac{ - 4}{2} = - 2 }} \\ [/tex]

Therefore points are;

(1, 2) and (-1, -2)

The probability that a randomly selected bottle is correctly placed AND is a Plastic #4 bottle is 0.25 or 25%

What is Conditional probability?

Conditional probability is the probability of an event occurring given that another event has occurred or is known to have occurred. It is denoted by P(A|B), which reads as "the probability of A given B."

The formula for conditional probability is:

P(A|B) = P(A and B) / P(B)

where P(A and B) is the probability of both events A and B occurring, and P(B) is the probability of event B occurring.

The total number of Plastic #2 bottles is 8 (correctly placed) + 5 (incorrectly placed) = 13.

The total number of Plastic #4 bottles is 5 (correctly placed) + 2 (incorrectly placed) = 7.

The probability that a randomly selected bottle is correctly placed AND is a Plastic #4 bottle is given by:

(number of Plastic #4 bottles correctly placed) / (total number of bottles)

So the probability is:

5/20 = 1/4 = 0.25

Therefore, the probability that a randomly selected bottle is correctly placed AND is a Plastic #4 bottle is 0.25 or 25%.

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Case 1: The constant c of the piecewise function is equal to 1 / 7.

Case 2: The value of the constant b of the piecewise function with the greater absolute value is equal to 20.

A piecewise function is function formed by two or more functions relative to intervals. A piecewise function is continuous if they do not have any jump on graph. For two functions, we must solve the following equation for the case of a piecewise function formed by two functions:

g(a) = h(a)

Case 1 - g(y) = c · y + 3, h(y) = c · y² - 3, a = 7

c · a + 3 = c · a² - 3

c · (a² - a) = 6

c = 6 / (a² - a)

c = 6 / (7² - 7)

c = 6 / 42

c = 1 / 7

The value of the constant c is equal to 1 / 7.

Case 2 - g(x) = b - 2 · x, h(x) = - 150 / (x - b), a = 5

b - 2 · a = - 150 / (a - b)

(b - 2 · a) · (a - b) = - 150

a · b - b² - 2 · a² + 2 · a · b = - 150

- b² + 3 · a · b - 2 · a² = - 150

b² - 3 · a · b + 2 · a² - 150 = 0

b² - 15 · b - 100 = 0

(b - 20) · (b + 5) = 0

b₁ = 20 or b₂ = - 5

The solution with the greater absolute value is b = 20.

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a)There are total 25 data values so for the given data, 100% data lies within 3 standard deviations of mean.

b). Second graph demonstrates that there is strong linear relationship between the theoretical and sample quantities

a) Here we have μ=61.52 and [tex]\sigma=4.58[/tex]

The 68-95-99.7% rule states that 68% of the data must be within one standard deviation of the mean. Thus, 68% of the data should fall between 61.52-4.58=56.94 and 61.52+4.58=66.1. 19 data values in the provided data are within one standard deviation of the mean. As there are a total of 25 data points, 76% of the data for the given data (19/25)*100=1 standard deviation of the mean.

The 68-95-99.7% rule states that 95% of the data should be within two standard deviations of the mean.

Specifically, 95% of the data should fall between 61.52+2*4.58=70.68 and 61.52-2*4.58=52.36. 24 data values in the provided data are within two standard deviations of the mean.

As there are a total of 25 data points, (24/25)*100=96% of the data for the given data is contained within two standard deviations of the mean.

The 68-95-99.7% rule states that 99.7% of the data should be within three standard deviations of the mean.

It follows that 99.7% of the data should fall between 61.52+3*4.58=75.26 and 61.52-3*4.58=47.78. 25 data values in the provided data are within three standard deviations of the mean.

As there are a total of 25 data points, (25/25)*100=100% of the data falls within three standard deviations of the mean for the given data.

Although not exactly, it appears that the distribution of height follows a normal distribution.

b) Both graphs demonstrate that the height distribution is essentially normal. Second graph demonstrates that there is strong linear relationship between the theoretical and sample quantities.

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The complete question is:

Heights of female college students. Below are heights of 25 female college students.

(a) The mean height is 61.52 inches with a standard deviation of 4.58 inches. Use this information to determine if the heights approximately follow the 68-95-99.7% Rule.

(b) Do these data appear to follow a normal distribution? Explain your reasoning using the graphs provided below.

Answer:

Step-by-step explanation:

Let weight of fourth parcel be x

Mean = Sum of all values/total number of values.

8.5 = 7.7 + 7.6 + 8.2 + x/4

8.5 = 23.5 + x/4

8.5 × 4 = 23.5 + x

34 = 23.5 + x

34 - 23.5 = x

10.5 = x

Therefore, weight of the fourth parcel will be 10.5 kg

As a result, both varieties of trees will be the same height after 9 years. We can change both equations to a = 9 to verify this: Height of the type A tree is 36 + 8(9) or 36 + 72 inches, whereas the height of the type B tree is 18 + 10(9) or 18 + 90 inches.

Trigonometry includes heights and distances, and it has numerous uses in practical daily life. It utilised to compute height of towers, structures, mountains, etc., and distance between any two objects such celestial bodies others. ,sys,s tos.as to .... and.

Let's use "a" to denote the number of years after planting the trees.

A type A tree will reach the following height after "a" years:

Height of type A tree = 36 + 8a

After "a" years, the height of a type B tree will be:

Height of type B tree = 18 + 10a

We must set the two types of trees' heights equal to one another and solve for "a" to determine when they will reach the same height:

36 + 8a = 18 + 10a

Subtracting 8a from both sides, we get:

36 = 18 + 2a

Subtracting 18 from both sides, we get:

18 = 2a

Dividing both sides by 2, we get:

a = 9

Therefore, after 9 years, both types of trees will be the same height.

To check this, we can substitute a = 9 into both equations:

Height of type A tree = 36 + 8(9) = 36 + 72 = 108 inches

Height of type B tree = 18 + 10(9) = 18 + 90 = 108 inches

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Question:

You have two types of trees to plant in your yard: type A trees are 36 inches tall and grow 8 inches per year, while type B trees are 18 inches tall and grow 10 inches per year. At what point in time will the trees be the same height? How tall will the trees be at that time?

Answer:

We will use mathematical induction to prove the formula for the sum of arithmetic sequences:

For n=1, we have:

∑j=1^1(a + (j-1)d) = a

On the other hand, we have:

n/2(2a + (n-1)d) = 1/2(2a) = a

Thus, the formula holds for n=1.

Assuming the formula holds for n=k, we will prove that it holds for n=k+1.

We have:

∑j=1^(k+1)(a + (j-1)d) = (a + kd) + ∑j=1^k(a + (j-1)d)

Using the formula for n=k, we can write:

∑j=1^k(a + (j-1)d) = k/2(2a + (k-1)d)

Substituting this back into the first equation, we have:

∑j=1^(k+1)(a + (j-1)d) = (a + kd) + k/2(2a + (k-1)d)

Simplifying the right-hand side, we get:

∑j=1^(k+1)(a + (j-1)d) = 1/2(2a + (2k+1)d)

But (k+1)/2(2a + kd + d) = 1/2(2a + (2k+1)d), so the formula holds for n=k+1.

Therefore, by mathematical induction, the formula for the sum of arithmetic sequences is proved.

The correct option b) [tex]\rm y = \sqrt{x+ 3} + 3[/tex] is a function of the given graph.

The graph οf a relatiοn is said tο reflect a functiοn if a vertical line drawn anywhere οn the graph οnly intersects the graph οnce. In the event when a vertical line can graph is nοt a representatiοn οf a functiοn if there are mοre than twο pοints οn it.

The graphs coordinate is at (-3, 3)

Lets put the value in all the given function to find the correct function

a. [tex]\rm y = \sqrt{x - 3} + 3[/tex]

Using (-3, 3) as x and y

[tex]\rm 3 = \sqrt{(-3) - 3} + 3[/tex]

[tex]\rm 3 = \sqrt{9} + 3[/tex]

[tex]\rm 3 \neq 3 + 3[/tex]

[tex]\rm y = \sqrt{x - 3} + 3[/tex] is not a function of graph.

b. [tex]\rm y = \sqrt{x+ 3} + 3[/tex]

Using (-3, 3) as x and y

[tex]\rm 3 = \sqrt{-3+ 3} + 3[/tex]

[tex]\rm 3 = \sqrt{0} + 3[/tex]

[tex]\rm 3 = 0 + 3[/tex]

[tex]\rm 3 = 3[/tex]

[tex]\rm y = \sqrt{x+ 3} + 3[/tex] is a function of the given graph.

The other two options are no the functions as cube root is used and the value of x wont satisfy there.

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The set of ordered pairs does not represent a function is the one in the third option.

{(-1,9), (-8, 5), (-1, 3), (-9, 1)}

A relation maps elements from one set, the domain, into elements of other set, the range.

Such that these mappings are of the form (x,y).

A function is a relation where each input is mapped into a single one output, then if you see a relation that has two points with the same value of x and different values of y, then that relation is not a function.

Particularly, if you look at the third option:

{(-1,9), (-8, 5), (-1, 3), (-9, 1)}

You can see that the first and second points have the same input and different outputs, then this is not a function, and that is the correct answer.

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In response to the stated question, we may state that As a result, the overall probability of an accurately picked drive-thru order across all chains is roughly 0.929, or 92.9%.

Probability theory is an area of mathematics that calculates the likelihood of an occurrence or a proposition being true. A risk is a number in the range of 0 and 1, whereas 1 implies certainty and a probability of roughly 0 indicates how likely an event seems to be to occur. Probability is a mathematical expression of the chance or chances that a given event will occur. Probabilities can alternatively be stated as integers between 0 and 1 or as % from 0% to 100%. the ratio of occurrences among equally likely choices that result in a certain event in comparison to all other outcomes.

Using the data in the table, we can compute the likelihood of a correct drive-thru order for each fast food chain, as well as the overall chance of an accurate order across all chains.

Divide the number of accurate orders by the total number of orders to find the chance of a randomly picked order being accurate at each chain:

P(accurate order) = 1246 / 1300 = 0.958 for McDonald's

P(accurate order) = 1020 / 1100 = 0.927 Taco Bell

P(accurate order) = 708 / 800 = 0.885 for Burger King

P(accurate order) = 940 / 1000 = 0.94 for Wendy's

P(adequate overall order) = 0.3 * 0.958 + 0.25 * 0.927 + 0.2 * 0.885 + 0.25 * 0.94 = 0.929

As a result, the overall likelihood of an accurately picked drive-thru order across all chains is roughly 0.929, or 92.9%.

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Two radicals are said to be radicals if they have the same indices and the radicand.

In mathematics, a radicand is an expression, a number, or a variable that is enclosed in a root symbol. The factor for which we are determining the root is quantity. As we study exponents and roots, the word "radicand" is utilised. Therefore, the radicand in 2 has a value of 2. Following are some radicand examples:

3√(pq) → pq is the radicand

√(a+b) → a + b is the radicand

4√15 → 15 is the radicand

A radical is a symbol used to represent a number's root. It is symbolised as. The word or phrase that appears after the radical symbol is known as the radicand. Hence, it may be claimed that the radical represents the radicand. Alternatively said, the radicand sign is √.

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Complete question:

Type the correct words in the blanks:

Two radicals are said to be radicals if they have the same               and the radicand.

The utility that maximizes the possible utility of both the agents Alice and Bob is equal to option D. $10.

Compare Alice's utility from each option and choose the one that maximizes her utility.

Let us consider each option,

If Alice offers Bob $0, her utility will be,

If XA > XB then

UA (XA , XB )= 0.3x3 + 0.72A

UA(10,0)

= 0.3(10)³ + 0.72(10)

= 307.2

If Alice offers Bob $5, Bob's utility will be,

UB(10,5)

= 0.314 + 0.72(5)

= 0.314 + 3.6

= 3.914

And Alice's utility will be,

UA(5,10)

= -0.32(5) + 1.3(10)

= 11.4

Total utility for both Alice and Bob will be,

UA(5,10) + UB(10,5)

= 11.4 + 3.914

= 15.314

If Alice offers Bob $2, Bob's utility will be,

UB(10,2)

= 0.314 + 0.72(2)

= 1.754

And Alice's utility will be,

UA(2,10)

= -0.32(2) + 1.3(10)

= 12.4

So the total utility for both Alice and Bob will be,

UA(2,10) + UB(10,2)

= 12.4 + 1.754

= 14.154

If Alice offers Bob $10, Bob's utility will be,

UB(10,10)

= 0.314 + 0.72(10)

= 7.514

And Alice's utility will be,

UA(10,10)

= 0.3(10)³ + 0.72(10)

= 307.2

So the total utility for both Alice and Bob will be,

UA(10,10) + UB(10,10)

= 307.2 + 7.514

= 314.714

Therefore, utility which maximizes the total utility for both Alice and Bob is given by option (D) $10.

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Step-by-step explanation:

2x + ay + 2 = 0

the gradient or slope of the line is the factor m of x in the form

y = mx + b

so let's transform the given equation into that form :

ay = -2x - 2

y = (-2/a)x - 2/a

we know that m = 1.

so,

-2/a = 1

-2 = a

As all the sides of the closed figure are equal to each other, the quadrilateral here is a square.

A square is a closed, two-dimensional (2D), object with four corners. With four sides and four vertices, a quadrilateral is referred to as a square. All four sides of a square are equal and parallel.

In other words, a square is a polygon or quadrilateral with four sides. An equiangular quadrilateral is a shape in which all of the angles are of equal size.

Here in the given figure, we can see a quadrilateral is given.

We can see that all the sides of the quadrilateral are given to be equal to each other.

We can conclude from the observation that the quadrilateral is a square as the sides are all equal to each other.

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Answer:

D.

Step-by-step explanation:

Answer: 811 adult tickets and 868 child tickets

Step-by-step explanation:

35x +20y = 44,620

add 35+20

divide the sum by 44,620 and

the answer

Answer:

if u want total price then,

=Rs.35×80=Rs.2800

The missing side is 30.

Three line segments that cross at three non-collinear locations to form a triangle constitute a triangle in geometry. The triangle's three line segments are referred to as its sides, and its three points of intersection as its vertices.

A triangle is a three-sided polygon formed by three line segments intersecting at three non-collinear points, and it can be classified based on the length of its sides and the measure of its angles.

Given figure, there are two lines ate parallel, that's why two triangles are similar triangle.

Assume that the missing side is x.

So that side ratio in similar triangle are equal;

14/20 = 21/x

So, x = 30.

Therefore, the missing side x is 30

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Triangle Three line segments that cross at three non-collinear locations to form a triangle constitute a triangle in geometry. According to the question the missing side is 30.

Three line segments that cross at three non-collinear locations to form a triangle constitute a triangle in geometry. The triangle's three line segments are referred to as its sides, and its three points of intersection as its vertices. A triangle is a three-sided polygon formed by three line segments intersecting at three non-collinear points, and it can be classified based on the length of its sides and the measure of its angles.

Given figure, there are two lines ate parallel, that's why two triangles are similar triangle.
Assume that the missing side is x.
So that side ratio in similar triangle are equal;
14/20 = 21/x

So, x = 30.
Therefore, the missing side x is 30

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Answer:

m = -5/8

Step-by-step explanation:

Slope = rise/run or (y2 - y1) / (x2 - x1)

Points (-1, -7) (-9, -2)

We see the y increase by 5 and the x decrease by 8, so the slope is

m = -5/8

The probability that a customer will actually make a valid warranty claim is 0.075.

A probability is a numerical representation of the likelihood or chance that a specific occurrence will take place. Both proportions ranging from 0 to 1 and percentages ranging from 0% to 100% can be used to describe probabilities.

The probability that a customer will make a valid warranty claim is the probability that the customer both uses the bike in the first year (which has a probability of 0.75) and discovers a defect (which has a probability of 0.10).

Using the multiplication rule of probability, the probability that both of these events occur is:

0.75 x 0.10 = 0.075

Therefore, the probability that a customer will actually make a valid warranty claim is 0.075.

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Method to list all non-isomorphic trees on n vertices is to add edges to a single vertex tree. Using A, B, C, D, E, we list 5 non-isomorphic trees on 6 vertices.

A by-hand method to give a list of all non-isomorphic trees on exactly n vertices is to start with a tree on n vertices and then generate all possible trees by adding edges between vertices that are not already connected.

For example, to find all non-isomorphic trees on 4 vertices, we can start with a single vertex and then add edges to form a tree with 2 vertices, then add edges to form a tree with 3 vertices, and finally add edges to form a tree with 4 vertices. We can then check each tree for isomorphism by comparing their adjacency matrices.

Using the method from (a), we can find all non-isomorphic trees on exactly six vertices by starting with a single vertex and adding edges until we have a tree on six vertices.

To ensure that we generate all possible trees, we can use the following five vertices: A, B, C, D, E. We can then generate all trees by adding edges between vertices that are not already connected, making sure to avoid creating cycles. After generating all trees, we can check for isomorphism by comparing their adjacency matrices.

The resulting list of non-isomorphic trees on six vertices, in alphabetical order, is shown. The tree 1 and tree 2 are the same. Also, trees 3, 4, and 5 are not isomorphic to each other or to trees 1 and 2.

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Cold fronts generally move faster than warm fronts because cold air is denser and thus, moves more quickly. Precipitation with a cold front typically covers a broader area, especially during the winter.

On the other hand, warm fronts move more slowly as they are characterized by the gradual lifting of warm air over colder air. Cold fronts also typically have steeper slopes than warm fronts. This is because the leading edge of a cold front is more abrupt.

With a steep rise in the cold air mass. In contrast, the leading edge of a warm front has a gentler slope as the warm air gradually rises over the colder air.

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Selection bias can creep into a study if subjects are picked (intentionally or not) according to some criterion and not randomly.

Selection bias occurs when the selection of study participants is not random and is instead influenced by certain criteria. This can result in a non-representative sample that does not accurately reflect the population being studied, leading to inaccurate conclusions. For example, if a study on the effectiveness of a medication only enrolls participants who are already known to respond well to that medication, the results may overestimate its effectiveness in the general population. To minimize selection bias, researchers should use random sampling techniques and carefully consider the inclusion and exclusion criteria .

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The inventory turnover ratio can be calculated by dividing the cost of goods sold by the average inventory value. In this case, the inventory turnover ratio is 0.5, and the correct answer is (D) 0.5.

The inventory turnover ratio measures the number of times a company sells and replaces its inventory during a period. It can be calculated by dividing the cost of goods sold by the average inventory value.

The inventory turnover ratio = Cost of goods sold / Average inventory value

In this case, the cost of goods sold is $600,000 and the average inventory value is $1,200,000.

Inventory turnover ratio = $600,000 / $1,200,000 = 0.5

Therefore, the inventory turnover ratio is 0.5, and the correct answer is (D) 0.5.

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Complete question:

If the average aggregate inventory value is $1,200,000 and the cost of goods sold is $600,000, which of the following is inventory turnover?

A)60

B)10.4

C)2

D)0.5

E)None of these

The population of interest is the group of students who submitted an application to the college in 2017.

A sample is a subset of a population that is selected and studied in order to make inferences or conclusions about the population. The sample is usually selected to be representative of the population in some way, so that the conclusions drawn from the sample can be generalized to the population as a whole.

The correct answer is C.

The purpose of the study is to determine why students who are interested in the college decide to enroll or not. Therefore, the population of interest is the group of students who submitted an application to the college in 2017.

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Answer

6255 pounds

8.34×750=6255lbs

To find the slope of a line that passes through two points, you can use the slope formula. The slope formula is:

Slope = (y2 - y1) / (x2 - x1)

Using the points given in your question, the slope formula to find the slope of the line is:

Slope = (2 - 8) / (4 - (-4))

Using the order of operations, the calculation of the slope formula is as follows:

Slope = -6 / 8

Therefore, the slope of the line passing through (-4, 8) and (4, 2) is -3/4.

The measurement of angle PCD in equilateral triangle  is 67.38°.

Let $s$ be the side length of the square $abcd$, and let $O$ be the center of the square. Then $OP = s/\sqrt{2}$.

Since triangle $ABP$ is equilateral, we have $\angle ABP = 60^\circ$ and $AP=BP=s$. Let $E$ be the foot of the perpendicular from $P$ to $AB$. Then $AE=BE=s/2$ and $EP=s\sqrt{3}/2$.

Since $EP$ is perpendicular to $AB$ and $AB$ is parallel to $CD$, we have $\angle PCD = \angle ACE$.

Since $OP$ is perpendicular to $AB$, we have $\angle OEP = \angle AEP = 30^\circ$. Also, $OE=OP/\sqrt{2}=s/2$.

Using the Pythagorean theorem in triangle $OCE$, we have

CE= [tex]\sqrt{(OE)^{2} + (OC)^{2}} = \sqrt{(s/2)^{2} + s^{2}} = s\sqrt{5}/2[/tex]

Therefore, $\sin \angle ACE = CE/CP = \sqrt{5}/2$. Thus,

∠PCD = ∠ACE = arcsin(√5/2) ≈ 67.38°

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