Let s > 0. Suppose that the lifetimes of a certain brand of transistor are identically distributed and independent random variables with probability distribution function F . These transistors are randomly selected, one at a time, and their lifetimes are measured. Let N be the number of transistors tested when a transistor is found to have a lifetime of greater than s hours. Let XN be the lifetime of that long-lasting transistor. Are XN and N independent random variables?