38. Delivery service. A company must decide which of two delivery services they will contract with. During a recent trial period they shipped numerous packages with each service and have kept track of how often deliveries did not arrive on time. Here are the data: Delivery Type of Number of Number of service service deliveries late packages Regular 400 12 Pack Rats Overnight 100 16 100 2 Boxes R Us Regular Overnight 400 28 a) Compare the two services' overall percentage of late deliveries. b) Based on the results in part a, the company has de- cided to hire Pack Rats. Do you agree they deliver on time more often? Why or why not? Be specific. c) The results here are an instance of what phenomenon?39. Graduate admissions. A 1975 article in the magazine Science examined the graduate admissions process at Berkeley for evidence of gender bias. The table below shows the number of applicants accepted to each of four graduate programs. Males accepted Females accepted (of applicants) (of applicants) 511 of 825 89 of 108 352 of 560 17 of 25 Program W N 137 of 407 132 of 375 22 of 373 24 of 341 Total 1022 of 2165 262 of 849 a) What percent of total applicants were admitted? b) Overall, were a higher percentage of males or females admitted? c) Compare the percentage of males and females admit- ted in each program. d) Which of the comparisons you made do you consider to be the most valid? Why