The General Social Survey asked 1294 people whether they performed any volunteer work during the past year. A total of 517 people said they did.

a. Find a point estimate for the proportion of people who performed volunteer work during the past year.

b. Construct a 95% confidence interval for the proportion of people who performed volunteer work during the past year.

c. A sociologist states that 50% of Americans perform volunteer work in a given year. Does the confidence interval contradict this statement? Explain.