A survey of 120 students is selected randomly on a large university campus. They are asked if they use a laptop in class to take notes. The result of the survey is that 60 of the 120 students responded"yes." An approximate 98%confidence interval is (0.394, 0.606). Complete parts a through d below.

a) How would the confidence interval change if the confidence level had been 90% instead of 98%?

b.How would the confidence interval change if the sample size had been 180instead of 120? (Assume the same sampleproportion.)

c.How would the confidence interval change if the confidence level had been 99% instead of 98%?

d.How large would the sample size have to be to make the margin of error half as big in the 98% confidenceinterval?