9.44      The recent default rate on all student loans is 5.2 percent. In a recent random sample of 300 loans at private universities there were 9 defaults. (a) Does this sample show sufficient evidence that the private university loan default rate is below the rate for all universities, using a left-tailed test at α = .01? (b) Calculate the p-value. (c) Verify that the assumption of normality is justified.

9.45      The Association of Flight Attendants/Communication Workers of America and National Con- sumers League conducted a poll of 702 frequent and occasional fliers and found that 442 respon- dents favored a ban on cell phones in flight, even if technology permits it. At α = .05, can we conclude that more than half the sampled population supports a ban? (Data are from Aviation Week and Space Technology 182, no. 15 [April 11, 2005], p. 14.)