Of n1 randomly selected engineering students at arizona state university, x1 owned an apple computer, and of n2 randomly selected engineering students at virginia tech, x2 owned an apple computer. let p1 and p2 be the probability that randomly selected asu and virginia tech engineering students, respectively, own apple computers. a. show that an unbiased estimate for p1 − p2 is (x1/n1) − (x2/n2). b. what is the standard error of the point estimate in part (a)? c. how would you compute an estimate of the standard error found in part (b)? d. suppose that n1 = 200, x1 = 150, n2 = 250, and x2 = 185. use the results of part (a) to compute an estimate of p1 − p2. e. use the results in parts (b) through (d) to compute an estimate of the standard error of the estimate.