What are 5 rules to follow in a science lab?
Answer:
Step-by-step explanation:
1. Wear safety glasses
2. Be accompanied by an adult
3. Wear proper lab clothing
4. Alert Lab instructor if an accident were to happen
5. Follow all instructions given by lab instructor
what is 20% of 30? how would you calculate it? please answer asap
Answer:
Working out 20% of 30
If you are using a calculator, simply enter 20÷100×30 which will give you 6 as the answer.
Step-by-step explanation:
Answer:
6Step-by-step explanation:
what is 20% of 30? how would you calculate it?
30 : 100 * 20 = 6
or
30 * 0.20 = 6
A soccer goalpost is to be made of 40 feet of
Jumber. The school has 27 feet. How much
umber should be purchases?
Answer:
13 more should be purchased.
40-27=13
Please take a look at the picture
[tex]\implies {\blue {\boxed {\boxed {\purple {\sf {C.\:None\:of\:the\:above.}}}}}}[/tex] ✔
[tex]\:\large{\boxed{\frak{ Step-by-step\:explanation: }}}[/tex]
A. [tex]x - ( - x) = -x[/tex]
Let us first solve for L. H. S.
We have,
[tex]x - ( - x)[/tex]
[tex] = x + x[/tex]
[tex] = 2x[/tex]
[tex]≠ - x[/tex]
[tex]≠ R. H. S. [/tex]
Hence, option A is incorrect.
B. [tex]0 - ( - x) = - x[/tex]
Solving for L.H.S. , we have
[tex] = 0 - ( - x)[/tex]
[tex] = + x[/tex]
[tex]≠ - x[/tex]
[tex]≠ R. H. S. [/tex]
Hence, option B is ruled out too.
Therefore, the correct answer is [tex]\sf\red{ option\:C}[/tex].
please help meeeee c:
Answer:
x = - 2
Step-by-step explanation:
Don't let the points disturb you. They are actually meant to confuse you.
please help me calculation completing square?
x²+2x-24=0?
Answer:
x = 4, -6
Step-by-step explanation:
x = 4, -6
Two decimal for 2597.58333
Answer:
2597. 58000 and this is the ans
Suppose `h\left(t\right)=-5t^{2}+10t+3`is an expression giving the height of a diver above the water (in meters), t seconds after the diver leaves the springboard.
a. How high above the water is the springboard? Explain how you know.
Answer:
Step-by-step explanation:
a) The height of the springboard above the water should be h(0) : Read, the height at t = 0
h(0) = -5(0) + 10(0) + 3
h(0) = 0 + 0 + 3
h(0) = 3
a) 3 meters
b) The time it takes the diver to hit water should be, the positive 0 solution for t. Remember, in a quadratic equation, there are two values for t where a parabola crosses the horizontal axis, which in this case would be t. Just by looking at the function, h(t) = -5t2 + 10t + 3 , one should be able to see that it cannot be factored easily, so it requires the Quadratic Formula to find the zeros ; x = -b ±√(b2-4ac) / 2a
Substitute t for x, and use the coefficients for a, b, c:
t = (-10 ± √((102 - 4(-5)(3)))/2(-5)
t = (-10 ±√(100 + 60))/-10
t = (-10 ±√160)/-10) ; Now factor the 160 to simplify:
t = (-10 ±√(10*16))/-10
t = (-10 ±4√10)/-10 ; Factor out leading coefficient of -2 from the numerator:
t = -2(5 ± 2√10)/-10
t = (5 ± 2√10)/5
Using a calculator to find the zeros, and disregarding the negative zero (because t starts at 0):
t ≈ 2.265
b) approx. 2.265 seconds for diver to hit water.
c) To find this, set the function equal to 3 to find what other value for t would be equal to 3 (we know one is 0).
-5tt + 10t + 3 = 3
-5t2 + 10t = 0 ; factor out t
t(-5t + 10) = 0
We know t = 0:
We also know that -5t + 10 = 0
-5t = -10
t = 2
c) 2 seconds. This is the time that diver would equal height of t=0 which is where he started, and where he equals the height of the springboard.
d and e) The peak of the dive (parabola), is determined using the formula h = -b/2a (Derived from the Quadratic Formula) to find the y value (in this case, the h value, answering e) and then using that result in the function to find the x value (in this case, the t value answering d) of the point where the parabola (dive path) reaches a maximum(height), or minimum(in upward opening parabolas).
h = -10/2(-5)
h = -10/-10
h = 1
h(1) = -5(1)2 + 10(1) + 3
h(1) = -5 + 10 + 3
h(1) = 8
d) At t = 1 second, diver will have reached peak of dive.
e) At t = 1 second, diver will have reached a maximum height of 8 meters.
help me please the drop down menu is the same for top and bottom i’m lost:(
Answer:
1) No solution
2) Infinitely many solutions
Step-by-step explanation:
1) No solution
0=2 is false.
2) Infinitely many solutions
2=2 is true because both sides are equal, hence, it is an infinite solution.
Hope this helps :)
a man walks for 45 minutes at a rate of 3 mi/h then jogs for 75 minutes at a rate of 5 mi/h then rests for 30 minutes and finally walks for 90 minutes at a rate of 3 mi/h. Write a piecewise-defined function expressing the distance he traveled as a function of time.
Answer:
Sorry need points
Step-by-step explanation:
If X is a factor of Y and Y is a factor of Z then X is a factor of Z. If so then how
PLS HELP HELP HELP HELP HELP HELP HELP !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
then z is a factor of x??? huh??
What is 11% of 96 students
Answer:
8.7
Step-by-step explanation:
8.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.78.7
A company produces electric insulators. The strength of the insulators is important since a broken insulator may cause a short circuit. Unfortunately, the strength varies significantly due to the material. Because of the expense, only a limited number of insulators could be tested. The engineers sampled 25 insulators (From a production run of 200), and conducted a destructive test to determine the force that was required to break the insulators. The mean value of this force was 1723 lbf with a sample standard deviation of 90 lbf. You may approximate the population standard deviation with the sample standard deviation for the following questions.
a. Determine if the population is large enough or if a finite population correction (FPC) factor is needed. If so, what is the FPC factor?
b. For 95% confidence, determine the margin of error (+ lbf)
c. For these conditions, estimate the range of the probable population mean. Provide lower and upper values. For 95% confidence, determine the margin of error ( Assume the same mean and sample standard deviation. What is one advantage and one disadvantage of using 50 insulators instead of 25 insulators?
d. lbf) if 50 insulators were tested.
Answer:
A company produces electric insulators. The strength of the insulators is important since a broken insulator may cause a short circuit. Unfortunately, the strength varies significantly due to the material. Because of the expense, only a limited number of insulators could be tested. The engineers sampled 25 insulators (From a production run of 200), and conducted a destructive test to determine the force that was required to break the insulators. The mean value of this force was 1723 lbf with a sample standard deviation of 90 lbf. You may approximate the population standard deviation with the sample standard deviation for the following questions. a. Determine if the population is large enough or if a finite population correction (FPC) factor is needed. If so, what is the FPC factor? b. For 95% confidence, determine the margin of error (+ lbf) c. For these conditions, estimate the range of the probable population mean. Provide lower and upper values. For 95% confidence, determine the margin of error ( Assume the same mean and sample standard deviation. What is one advantage and one disadvantage of using 50 insulators instead of 25 insulators? d. lbf) if 50 insulators were tested.
Step-by-step explanation:
The length of a rectangle is three times its width. if the area of the rectangle is 75 in2, find its perimeter.
Answer:
40 in
Step-by-step explanation:
For a width of w, the length is 3w and the area and perimeter are ...
A = LW = (3w)(w) = 3w^2
P = 2(L+W) = 2(3w +w) = 8w
We are given the area, so we can find w to be ...
75 in^2 = 3w^2
25 in^2 = w^2 . . . . . divide by 3
5 in = w . . . . . . . . . square root
Then the perimeter is ...
P = 8w = 8(5 in) = 40 in
help any body plzs i will give brianlyest
- BRAINLIEST answerer
Who is the general information of accounting
Answer:
General accounting essentially refers to general ledger collection and accounting activities that include account charges in credits and debits and documenting financial statements for a quarter, calendar or fiscal year.
g A long-term study has revealed that a test for cancer in men is very effective. The study shows that 89% of the men for which the test is positive actually have cancer. If a man selected at random tests positive for cancer with this test, what is the probability that he does not have cancer
Which equation represents a line that is parallel to the line 4x-3y=15
1) y = -4/3x - 4
2) y = -3/4x - 2
3) y = 4/3x + 2
4) y = 3/4x - 6
Answer:
1
Step-by-step explanation:
because... it is
Soraya earned $40 in October. She earned $50 in
November.
What is the percent increase or decrease in Soraya's monthly earnings?
A. 15% decrease
B. 30% increase
C. 25% increase
D. 20% decrease
25% increase.
Explanation: 25% of $40 is $10. You add $10 to $40 you get $50.
Zhao Co. has fixed costs of $416,000. Its single product sells for $185 per unit, and variable costs are $121 per unit. Compute the level of sales in units needed to produce a target (pretax) income of $128,000.
9514 1404 393
Answer:
8,500 units
Step-by-step explanation:
The contribution margin from each unit is ...
$185 -121 = $64
To accumulate a total contribution that will cover the fixed costs and the desired income, you require sales of ...
($416,000 +128,000)/($64/unit) = 8,500 units
Pls help I’ll brainlest ASAP
Make this sentence better the building is old and ugly
Answer:
the building is aged and unique.
Help please please need quick
1cm +4cm+2cm+1.5cm+2.5cm
find its perimeter
Answer:
11 cm
Step-by-step explanation:
add whole numbers
1 + 4 + 2 = 7
add decimal numbers
1.5 + 2.5 = 4
add the answers
7 + 4 = 11
have a splendid day <3
Answer:
11cm
Step-by-step explanation:
To find perimeter, you simply just add each of the side lengths.
To make this easier to read, lest group some of the terms
1cm + 4cm = 5cm
2cm + 1.5cm = 3.5cm
5cm + 3.5cm = 8.5cm
8.5cm + 2.5cm = 11cm
The five terms are bolded to make sure that we added each term in the sum.
The slope of the line whose equation is 2x + 5y + 1 = 0 is
Answer:
the slope is -2/5
Step-by-step explanation:
Solve for y.
2x + 5y + 1 = 0
5y = -2x - 1
y = -2/5 x - 1/5
Compare to
y = mx + b, where m is the slope.
m = -2/5
Answer: the slope is -2/5
Can someone please explain this to me please?
Will give brainly if you actually answer the question
Answer:
Step-by-step explanation:
24)
3x - 10 > 2
3x - 10 + 10 > 2 + 10
3x > 12
3x/3 > 12/3
x > 4
5x - 15 < -5
5x - 15 + 15 < -5 + 15
5x < 10
5x/5 < 10/5
x < 2
B) x > 4 or x < 2
25) 1.5/60 = 12/x
x = 12(60) / 1.5
x = 480
B) 480 miles
This distance from Old Faithful to Mammoth Hot Springs is actually about 52 miles by road, so there must have been MASSIVE number of road closures to get this result...or else their scale is incorrect. 1.5 inch to 6.0 miles would be a much more accurate scale making the distance 48 miles.
A previous survey of Washington residents showed that 18% of residents accessed a state park within the last 12 months. This year, the state would like to re-administer the survey, but wants to be sure the Margin of Error in their new study will be at most 4%. Assuming they believe the previous survey's results were reliable, how many samples should they take to ensure their Margin of Error is at most 4% if they plan to analyze the data using a 95% confidence interval
Using the z-distribution for the margin of error, it is found that 355 samples should be taken.
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which z is the z-score that has a p-value of [tex]\frac{1+\alpha}{2}[/tex].
The margin of error is given by:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
The estimate is of 18%, hence [tex]\pi = 0.18[/tex].
95% confidence, hence [tex]\alpha = 0.95[/tex], z is the value of Z that has a p-value of [tex]\frac{1+0.95}{2} = 0.975[/tex], so [tex]z = 1.96[/tex].
The minimum sample size is n for which M = 0.04, hence:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.04 = 1.96\sqrt{\frac{0.18(0.82)}{n}}[/tex]
[tex]0.04\sqrt{n} = 1.96\sqrt{0.18(0.82)}[/tex]
[tex]\sqrt{n} = \frac{1.96\sqrt{0.18(0.82)}}{0.04}[/tex]
[tex](\sqrt{n})^2 = \left(\frac{1.96\sqrt{0.18(0.82)}}{0.04}\right)^2[/tex]
[tex]n = 354.4[/tex]
Rounding up, 355 samples should be taken.
A similar problem is given at https://brainly.com/question/14936818
3. If Superman can fly .25 miles in 8 seconds, how far could he fly in...
(a) 40 seconds?
Answer:
1.25 miles
Step-by-step explanation:
0.25 miles = 8 seconds
x miles = 40 seconds
0.25/8 = x/40
0.25 * 40 = 8x
10 = 8x
x = 1.25
-Chetan K
Solve the inequality: x + 5 < 7 x < 3 , x > -2. , x > 12. , x < 2
Answer:
(d) x < 2
Step-by-step explanation:
Subtract 5 from both sides of the inequality, the same way you would if it were an equation.
x +5 < 7 . . . . . . given
x +5 -5 < 7 -5 . . . . . show subtraction of 5
x < 2 . . . . . the solution
The numbers and letters on a license plate are determined by the state that issues the license
plate. Suppose a state had a system that used 5 letters and 2 digits for a total of 7 characters on
a license plate. How many different license plates can this system produce?
297, 034, 400
594, 068, 800
1, 188, 137, 600
O 2, 376, 275, 200
Find the domain of the function.
f(x) = -5x + 3
Enter a problem...
Calculus Examples
Popular Problems Calculus Find the Domain and Range f(x)=5x-3
f
(
x
)
=
5
x
−
3
The domain of the expression is all real numbers except where the expression is undefined. In this case, there is no real number that makes the expression undefined.
Interval Notation:
(
−
∞
,
∞
)
Set-Builder Notation:
{
x
|
x
∈
R
}
The range is the set of all valid
y
values. Use the graph to find the range.
Interval Notation:
(
−
∞
,
∞
)
Set-Builder Notation:
{
y
|
y
∈
R
}
Determine the domain and range.
Domain:
(
−
∞
,
∞
)
,
{
x
|
x
∈
R
}
Range:
(
−
∞
,
∞
)
,
{
y
|
y
∈
R
}
