For #31 on page 252 with 83% rather than 82%, the proportion of 100 college graduates who believe their degree was a good investment is a random variable. Thus it has a mean. What is the value of the mean? 31. A survey found that 82% of college graduates believe their degree was a good investment. Suppose a random sample of 100 college graduates is taken. a. What are the expected value and the standard error for the sampling distribution of the sample proportion? b. What is the probability that the sample proportion is less than 0.80? c. What is the probability that the sample proportion is within 0.02 of the population proportion? Provide an answer with 2 decimal point