High blood pressure has been identified as a risk factor for heart attacks and strokes. The proportion of U.S. adults with high blood pressure is 0.4. A sample of 40 U.S. adults is chosen. Use the TI-84 Plus Calculator as needed. Round the answer to at least four decimal places.

a. Find the probability that the proportion of individuals in the sample of who have high blood pressure is between 0.21 and 0.32.

b. Find the probability that less than 22% of the people in the sample of 78 have high blood pressure.

c. Would it be unusual if more than 32% of the individuals in the sample of 78 had high blood pressure?