Answer:
The rate of change in surface area when r = 20 cm is 20,106.19 cm²/min.
Step-by-step explanation:
The area of a sphere is given by the following formula:

In which A is the area, measured in cm², and r is the radius, measured in cm.
Assume that the radius r of a sphere is expanding at a rate of 40 cm/min.
This means that 
Determine the rate of change in surface area when r = 20 cm.
This is
when
. So

Applying implicit differentiation.
We have two variables, A and r, so:



The rate of change in surface area when r = 20 cm is 20,106.19 cm²/min.
Answer: LAST OPTION
Step-by-step explanation:
The complex numbers shown have the form:

By definition, the distance can the distance of the complex number from the origin on the complex plane can be calculated with the formula shown below:

Substitute values of each option. Then:
1) 
2) 
3) 
4)
(CORRECT OPTION)
The given polyn. is not in std. form. To answer this question, we need to perform the indicated operations (mult., addn., subtrn.) first and then arrange the terms of this poly in descending order by powers of x:
P(x) = x(160 - x) - (100x + 500)
When this work has been done, we get P(x) = 160x - x^2 - 100x - 500, or
P(x) = -x^2 + 60x - 500
So, you see, the last term is -500. This means that if x = 0, not only is there no profit, but the company is "in the hole" for $500.
Answer:
34/100
Step-by-step explanation: