A spherical snowball, related rates

Question

A spherical snowball is melting. Its radius is decreasing at 0.8 cm per hour when the radius is 20 cm. How fast is its volume decreasing at that time?

NOTE: Enter the exact value or round to three decimal places.

The volume is decreasing by _____ cm^3 per hour.

I have been trying this for a while, I have tried the answers -1280π and -4021.239, however, both of these answers are incorrect. Could anyone please solve this step by step and explain. I am on my final attempt, please help.

Answer 1

I'm getting the same answer. I believe the issue may be the negative, which in this case becomes a double negative. Because the answer statement explicitly says decreasing, there is no need to include the negative with the number. (Similarly, the problem statement says "decreasing at 0.8 cm per hour" rather than "decreasing at -0.8 cm per hour.")