A survey of 170 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 68 of the 170 students responded "yes." An approximate 95% confidence interval is (0.326, 0.474). Complete parts a through d below. a) How would the confidence interval change if the confidence level had been 90% instead of 95% ? The new confidence interval would be The new confidence interval would be (). (Round to three decimal places as needed.) Suppose you want to estimate the proportion of traditional college students on your campus who own their own car. From research on other college campuses, you believe the proportion will be near 25%. What sample size is needed if you wish to be 98% confident that your estimate is within 0.02 of the true proportion? A sample size of is needed. (Round up to the nearest whole number.)