Answer: A. 
B. A'(5) = 1.76 cm/s
Step-by-step explanation: <u>Rate</u> <u>of</u> <u>change</u> measures the slope of a curve at a certain instant, therefore, rate is the derivative.
A. Area of a circle is given by

So to find the rate of the area:


Using 

Then
![\frac{dA}{dt}=2.\pi.r.[\frac{726}{(t+11)^{3}}]](https://tex.z-dn.net/?f=%5Cfrac%7BdA%7D%7Bdt%7D%3D2.%5Cpi.r.%5B%5Cfrac%7B726%7D%7B%28t%2B11%29%5E%7B3%7D%7D%5D)
![\frac{dA}{dt}=2.\pi.[3-\frac{363}{(t+11)^{2}}].\frac{726}{(t+11)^{3}}](https://tex.z-dn.net/?f=%5Cfrac%7BdA%7D%7Bdt%7D%3D2.%5Cpi.%5B3-%5Cfrac%7B363%7D%7B%28t%2B11%29%5E%7B2%7D%7D%5D.%5Cfrac%7B726%7D%7B%28t%2B11%29%5E%7B3%7D%7D)
Multipying and simplifying:

The rate at which the area is increasing is given by expression
.
B. At t = 5, rate is:




At 5 seconds, the area is expanded at a rate of 1.76 cm/s.
Answer:
<h2>$1380.2</h2>
Step-by-step explanation:
Step one:
given data
weekly earnings= $375
Commission is 4% of sales.= 0.4
supposing sale is x, and the total earning is y
the expression for the total earning will be
y=375+0.4x
Step two:
for x= 2513, y will be
y=375+0.4(2513)
y=375+1005.2
y=1380.2
<em><u>Hence her total earnings for the week will be $1380.2</u></em>
Answer:
x=25
Step-by-step explanation:
since this is a triangle you would add up all the measure of this and set it equal to 180. 90 is the side with the box. so it would be 2x+15+x+90=180 then solve for x and you would get your answer.
Answer:
5.5
Step-by-step explanation:
B is the midpoint of AC, D is the midpoint of CE
This means that CE = 1/2 AE
CD = 1/2 ( 11)
CD = 5.5
1.1=1
2.2=4
3.3=9
4.4=16
5.5=25
6.6=36
7.7=49
8.8=64
9.9=81
10.10=100
11.11=121
12.12=144
13.13=169