The CDC reports that 25% of baby boys 6-8 months old in the United States weigh more than 20 pounds. A sample of 16 babies is studied. a. What is the probability that exactly 5 of them weigh more than 20 pounds? b. What is the probability that fewer than 3 weigh more than 20 pounds? c. What is the mean number who weigh more than 20 pounds in a sample of 16 babies aged 6- 8 months? d. What is the standard deviation of the number who weight more than 20 pounds in a sample of 16 babies aged 6-8 months? Round your answer to four decimal places.