88. A circular sampling region with radius X is chosen by a biologist, where X has an exponential distribution with mean value 10 ft. Plants of a certain type occur in this region according to a (spatial) Poisson process with rate .5 plant per square foot. Let Y denote the number of plants in the region.

a. Find and .

b. Use part

(a) to nd E(Y).

c. Use part

(a) to nd V(Y).