I'm assuming you're subtracting. It would be 3.9. The second one would be 0.65.
0.08 cm/min
Step-by-step explanation:
Given:

Find
when diameter D = 20 cm.
We know that the volume of a sphere is given by

Taking the time derivative of V, we get

Solving for
, we get


Answer:
-2/3x+6
Step-by-step explanation:
The answer to this equation is
x= 1, -3