Determine the rate at which the surface area is changing with respect to time at t=2 min, assuming that r = 3 at t = 0
Assume that the radius r of a sphere is expanding at a rate of 14 in / min. Its surface area is 4(pi)r^2
Ds/dt= 4pi2rdr/dt
i got 4pi2(28)(14)
is that right or would the radius be different at t = 2 min