Among live deliveries, the probability of a twin birth is .02. (a) in 2,000 live deliveries, what is the probability of at least 50 twin births? (use excel or appendix c to calculate probabilities. round standard deviation to 2 decimal places. round your answer to 4 decimal places.) probability (b) fewer than 35? (use excel or appendix c to calculate probabilities. round standard deviation to 2 decimal places. round your answer to 4 decimal places.)