)Suppose 1, 2, . . . 8 are i.i.d. random variables following common exponential distribution with common mean 1. Define N(t) = P8 i=1 I(i > t). Then {N(t), t [0, )} is a pure death process. Specify the rates of this pure death process and find the value of s such that the time to extinction is greater than s with (1/2)1/8 chance.