A survey of U.S. adults found that 32% have an online account with their healthcare provider. You randomly select 70 U.S. adults and ask them whether they have an online account with their healthcare provider. Find the probability that the number who have an online account with their healthcare provider is 

(a) At most 15, 

(b) Exactly 25, and 

(c) Greater than 30. Identify any unusual events. Explain.

Determine whether you can use a normal distribution to approximate the binomial distribution. If you can, use the normal distribution to approximate the indicated probabilities and sketch their graphs. If you cannot, explain why and use a binomial distribution to find the indicated probabilities.