Please help me my little sister and i don’t understand!!

Answer:

(i) The value of m when t = 30 is 13.2

(ii) The value of t when the mass is half of its value at t=0 is 34.7

(iii) The rate of the mass when t=50 is -0.18            

Step-by-step explanation:

(i) The m value when t = 30 is:

[tex] m = 24e^{-0.02t} = 24e^{-0.02*30} = 13.2 [/tex]

Then, the value of m when t = 30 is 13.2

(ii) The value of the mass when t=0 is:

[tex] m_{0} = 24e^{-0.02t} = 24e^{-0.02*0} = 24 [/tex]    

Now, the value of t is:

[tex] ln(\frac{m_{0}/2}{24}) = -0.02t [/tex]

[tex] t = -\frac{ln(\frac{24}{2*24})}{0.02} = 34.7 [/tex]

Hence, the value of t when the mass is half of its value at t=0 is 34.7

(iii) Finally, the rate at which the mass is decreasing when t=50 is:

[tex] \frac{dm}{dt} = \frac{d}{dt}(24e^{-0.02t}) = 24(e^{-0.02t})*(-0.02) = -0.48*                            (e^{-0.02*50}) = -0.18 [/tex]

Therefore, the rate of the mass when t=50 is -0.18.

I hope it helps you!                  

Answer:

2m^3n^3

Step-by-step explanation:

Let us start with the number parts

36 , 2 and 4

2 is common here as it can divide all

The smallest m factor is m^3 so it is common for all

The smallest n factor is n^3 which is also common for all

So, we have the greatest common factor as;

2 * m^3 * n^3 = 2m^3n^3

Step-by-step explanation:

[tex]here \: is \: your \: solution : - \\ \\ GIVEN \: \: -:- \\ \\ = > \: area \: of \: circle \: = 616 \: m {}^{2} \\ \\ \ = > pi = 22 \div 7 \\ \\ = > we \: need \: to \: find \: radius \: \\ \\ = > area \: of \: circle \: = \pi \: r {}^{2} \\ \\ = > \: \pi \: r {}^{2} = 616 \: m {}^{2} \\ \\ = > \: r {}^{2} \times (22 \div 7) = 616 \\ \\ = > \: r {}^{2} =( 616 \times 7) \div 22 \\ \\ = > \: r { }^{2} = 4312 \div 22 \\ \\ = > r {}^{2} = 196 \\ \\ = > \: r = \sqrt{196} \\ \\ = > \: r = 14 \: \: \: (ANSWER✓✓✓) \\ \\ HOPE \: IT \: HELPS \: YOU \: (◕ᴗ◕✿)[/tex]

From online research, the article is;

As days get shorter and colder in the autumn, chlorophyll molecules break down. Leaves quickly lose their green color. Some leaves begin to look yellow or orange because they still contain pigments called carotenoids. One such pigment, carotene, gives carrots their bright-orange color.

But red is special. This brilliant color appears only because the leaves of some plants, including maples, actually produce new pigments, called anthocyanins.

That’s a strange thing for a plant to do without a reason, says Bill Hoch of the University of Wisconsin in Madison. Why? Because it takes a lot of energy to make anthocyanins.

Why red?

To figure out the purpose of the red pigment, Hoch and his coworkers bred mutant plants that can’t make anthocyanins and compared them with plants that do make anthocyanins. They found that plants that can make red pigments continue to absorb nutrients from their leaves long after the mutant plants have stopped.

This study and others suggest that anthocyanins work like a sunscreen. When chlorophyll breaks down, a plant’s leaves become vulnerable to the sun’s harsh rays. By turning red, plants protect themselves from sun damage. They can continue to take nutrients out of their dying leaves. These reserves help the plants stay healthy through the winter.

The more anthocyanins a plant produces, the redder its leaves become. This explains why colors vary from year to year, and even from tree to tree. Stressful conditions, such as drought and disease, often make a season redder.

Now, Hoch is breeding plants for a new set of experiments. He wants to find out whether turning red helps plants survive cold weather.

“There’s a clear correlation between environments that get colder in the fall and the amount of red produced,” he says. “Red maples turn bright red in Wisconsin. In Florida, they don’t turn nearly as bright.”

More protection

Elsewhere, scientists are looking at anthocyanins in other ways. A recent study in Greece, for instance, found that as leaves grow redder, insects eat them less. On the basis of this observation, some scientists argue that red pigments defend a plant against bugs.

Leaves may turn red in the autumn to protect themselves from the sun’s ultraviolet rays.

J. Miller

Hoch rejects that theory, but Lee thinks that it might make sense. He points out that red leaves contain less nitrogen than green ones do. “It may actually be that insects avoid red leaves because they’re less nutritious,” Lee says.

However, “it’s pretty confusing at this point,” Lee admits. “People debate back and forth.”

To settle the debate, scientists will need to look at more species under more conditions, Lee says. So, he’s now researching leafy plants rather than trees. He’s especially interested in tropical plants, whose leaves turn red when they’re young rather than old.

Answer:

As seen in the Explanation, different people have given reasons why bright red leaves in the fall help protect the trees in the winter. Thus, there is sufficient evidence to conclude that bright red leaves in the fall help protect the trees in the winter.

Step-by-step explanation:

From the article, we can see that Hoch and his coworkers carried out an experiment on mutants and they discovered that plants that can make red pigments tend to continue absorbing nutrients from their leaves a long time after the mutant plants have stopped.

This study and other believe that plants make anthocyanins which acts as a kind of sunscreen to the plants. They also discovered that by the plants turning red, they protect themselves from sun damage

Also, we see that some scientists in Greece found out that as leaves grow redder, insects eat them less and they argued that red pigments defend a plant against bugs and as such Leaves may turn red in the autumn to protect themselves from the sun’s ultraviolet rays.

My Answer: One study said that anthocyanins are pigments that make leaves turn red. And some trees don’t absorb as many nutrients as trees with red leaves. That particular study focused on trees that don’t produce anthocyanins. So i believe there's some evidence, but not a definitive conclusion.

Edmentum Answer: There’s some evidence, but not a definitive conclusion. One study focused on trees that don’t produce anthocyanins. Anthocyanins are pigments that make leaves turn red. The study said that these trees don’t absorb as many nutrients as trees with red leaves.

Another study found that insects are generally not inclined to eat red leaves on trees. There seems to be a trend that suggests that red leaves are important for the trees’ survival in the fall. This trend needs to be validated by conducting more tests.

Step-by-step explanation:

Paraphrased

Answer:

810

Step-by-step explanation:

(-5)×(-6) = 30

9*3 = 27

27*30 = 810

Answer:

The answer is 90cm

Step-by-step explanation:

Hello,

Lateral area = (3+3+3+3)*6=4*3*612*6=72 (cm²)

Bases area= 2*3²=18 (cm²)

Total area= 72+18=90 (cm²)

Answer:

9 : 7

Step-by-step explanation:

Given

4.5 : 3 [tex]\frac{1}{2}[/tex] ( multiply both parts by 2 to clear the fractions )

= 9 : 7

Answer:

A 2

B 1

C 4

D 3

Step-by-step explanation:

( ) means not including (also used for infinity)

[ ] means including

The answer choices are in interval form, showing all the possible answer choices between two numbers and if the answer choice includes or excludes a number using the () []

Explanation for A:

x < 7.8 means x won't include 7.8 since the symbol is "less than" and not "less than or equal to".

x can be anything, it just has to be less than 7.8, so the answer is:

2 (-infinity, 7.8)

Explanation for B:

x <= 7.8 means x will include 7.8 since the symbol means "less than or equal to".

x can be anything, it just has to be less than or equal to 7.8, so the answer is:

1 (-infinity, 7.8]

Explanation for C:

x >= 7.8 means x will include 7.8 since the symbol means "greater than or equal to".

x can be anything, it just has to be greater than or equal to 7.8, so the answer is:

4 [7.8, infinity)

Explanation for D:

x > 7.8 means x won't include 7.8 since the symbol means "greater than" and not "greater than or equal to".

x can be anything, it just has to be greater than 7.8, so the answer is:

3 (7.8, infinity)

Hope it helps (●'◡'●)

Answer:

A:2 B:1 C:4 D:3

Step-by-step explanation:

Answer:

Quadratic equations of second degree.

[tex]{ \bf{a {x}^{2} + bx + c = 0}}[/tex]

Quadratic equations of third degree.

[tex]{ \bf{a {x}^{3} + {bx}^{2} + cx + d = 0}}[/tex]

Answer:

8x +120= 400

Step-by-step explanation:

Let the number of hours Max worked over the summer be x.

Assuming that he had $0 in his bank at the start of summer,

Total savings= 8(number of hours) +120

400= 8x +120

8x +120= 400

To find the value of x, first bring all the constants to one side of the equation.

8x= 400 -120

Simplify:

8x= 280

Divide both sides by 8:

x= 280 ÷8

x= 35

∴ Max worked for 35 hours over the summer.

Step-by-step explanation:

Hello,

Let's say a the  first term and r the ratio  of the G.P.

[tex]u_1=a=81\\u_2=a*r\\u_3=a*r^2\\u_4=a*r^3\\\\\dfrac{u_4}{u_1} =\dfrac{a*r^3}{a} =r^3=\dfrac{24}{81} =\dfrac{8}{27} \\\\r=\sqrt[3]{\dfrac{8}{27} } \\\\\boxed{r=\dfrac{2}{3}}\\[/tex]

Answer:

8050 m²

Step-by-step explanation:

We can divide the diagram up into two components: a rectangle with a width of 60 m and a height of 80 m, and a triangle with a base of 130 m (190 - 60) and a height of 50 m (80 - 30).

The area of the rectangle:

A = lw

A = 60 m (80 m)

A = 4800 m²

The area of the triangle:

A = 1/2 b*h

A = 1/2 (130 m) (50 m)

A = 1/2 (6500 m²)

A = 3250 m²

Now, we can add the areas of the two separate components:

A = 4800 m² + 3250 m²

A = 8050 m²

18 - (-f) = 91

Subtracting a negative value changes to addition:

18 + f = 91

Subtract 18 from both sides:

F = 73

Answer:

f = 73

Step-by-step explanation:

Solve for f

18 - ( - f ) = 91

18 + f = 91

18 - 18 + f = 91 - 18

f = 73

Answer:

[tex]110 in^{2}[/tex]

Step-by-step explanation:

[tex]===========================================[/tex]

Formulas:

Area of a rectangle/square:

[tex]A=lw[/tex]

[tex]===========================================[/tex]

Squares(2):

5*5=25

Multiply by 2

50 in.

Rectangles(4):

5*3=15

Multiply by 4.

60 in.

Total:

Add.

50+60= 110 in2

I hope this helps!

Step-by-step explanation:

Answer:

The final result is 7/10

the "divisions" (divisor) is 1/10

thus the answer is 7/10 ÷ 1/10

the actual operation ....

"to divide fractions we INVERT and Multiply"

7/10 * 10/1 = 70/10 = 7

there are 7 arrows going to the right

Step-by-step explanation:

Answer:

991

Step-by-step explanation:

We are looking for a number that is one more than a multiple of 9(denoted by the 9k) and is a three digit number. We can start by looking for 3-digit number divisible by 9 which are close to 1,000, since that is the next number larger than the largest three-digit number. We can tell that 999 is divisible by 9 because when divided it does not leave a remainder(you can also figure this out with divisibility tricks). We add one to get 1,000. This is not a three-digit number,  so we need to look for a smaller multiple of 9. Subtracting 9 from 999, we get the next largest multiple of 9. We can add 1, and this time, the number, 991, is a three digit number, and the largest that can be in the form 9k + 1.

Answer:

D

Step-by-step explanation:

Look for the intersection point of the two graphs

Another way:

You can just substitute each pair in both equations and u will find that d is the correct answer

Answer:

8 m

-----------------Work--------------

2*3 = 6

Ratio

2*4 = 8

Answer: 7.7 miles

Step-by-step explanation:

2.5x + 5.75 = 25 (x = each mile traveled)

2.5x = 25 - 5.75

2.5x = 19.25

x = 7.7 miles

Given:

Prime numbers can be expressed as a sum and difference of 2 prime numbers.

To find:

The prime numbers that can be expressed as a sum and difference of 2 prime numbers.

Solution:

Prime numbers are the positive integers which are greater than 1, divisible by only 1 and itself.

Prime numbers are 2, 3, 5, 7, 11, 13, 17, 19,... .

Only 2 is the even prime number.

The sum and difference of two odd integers is always an even number. So, we need to take one even prime number and one odd prime number to add and subtract the numbers to get a prime number.

[tex]2+3=5[/tex]

[tex]7-2=5[/tex]

Therefore, 5 is the only prime number that can be expressed as a sum and difference of 2 prime numbers.

Answer:

mine ended june 9th but i got summer school for 2 classes lol

School ended the 15 of June but I'm in summer school rn it ends this Friday

Answer:

y < -7

Step-by-step explanation:

You balance it like a normal equation:

8y + 3 > 15y + 52

8y + 3 (-8y) > 15y + 52 (-8y)

3 (-52) > 7y + 52 (-52)

-49 (÷7) > 7y (÷7)

y < -7

Step-by-step explanation:

If the volume of a cubical room is 2700 cm³ .

l³=2700

l=3 (100)⅓

Answer:

{5, 6, 7}

Step-by-step explanation:

When we have a given relation, the domain is the set of inputs, and the range as the set of the outputs.

so for a function f(x), and a domain {a. b. c}

The range is:

{f(a), f(b), f(c)}

In this case, we have:

f(x) = x + 6

and the domain is {-1, 0, 1}

Then the range is:

{ f(-1), f(0), f(1) }

{-1 + 6, 0 + 6, 1 + 6}

{5, 6, 7}

The correct option is the third one.

Answer:

22 people were born in the uk  (66 ÷ 360) × 120=22

Step-by-step explanation:

Using the pie chart, the fraction of people born in the UK, is: 7/30.

A pie chart is a graphical representation used to describe the composition of a data using degrees or percentages.

84° is given as the number of people that were born in the UK.

That's about: 84/360 × 120 = 28 people.

28 out of 120 people would give us a fraction of: 28/120 = 7/30.

Learn more about pie chart on:

https://brainly.com/question/26851221

#SPJ2