Question

Please please please help :( am i correct?

A high-altitude spherical weather balloon expands as it rises due to the drop in atmospheric pressure. Suppose that the radius r increases at the rate of 0.02 inches per second and that r = 36 inches at time t = 0. Determine the equation that models the volume V of the balloon at time t and find the volume when t = 360 seconds.

a. V(t) = 4pi(0.02t)2; 651.44 in.3

b. V(t) = 4pi(36 + 0.02t)2; 1,694,397.14 in.3

c. V(t) =4pi(0.02t)^3/3 ; 4690.37 in.3

d. V(t) = 4pi(36+0.02t)^3/3; 337,706.83 in.3

I chose D. Is this correct?