Let Z be a nonnegative random variable that satisfies E[Z4]=4 . Apply the Markov inequality to the random variable Z4 to find the tightest possible (given the available information) upper bound on P(Z≥2) .

Question

Let  Z  be a nonnegative random variable that satisfies  E[Z4]=4 . Apply the Markov inequality to the random variable  Z4  to find the tightest possible (given the available information) upper bound on  P(Z≥2) .