Hello! I need help with following probability problem. Thank you in advance..!

Let X1, X2, . . . be nonnegative i.i.d. random variables with E( Xk) = 3 and Var(Xk) = 1. (a) (2 points) Use Markov's inequality to give an upper bound on P(X1 2 5). (b) (2 points) Use Chebyshev's inequality to estimate P(| X1 - 3| > 2). (c) (5 points) Give a number n so that P( X 1 + . . . + Xn - 3 2 2)