An airline wants to survey customers about their overall satisfaction. They take a random sample of 1{,}0001,0001, comma, 000 customers who have flown in the past month and email them a survey. The email also offers those who complete the survey a \$25$25dollar sign, 25 gift card that can be used almost anywhere. Which of these is the best example of nonresponse bias?

Question 1 of 10 2 points different groups of 50 graduates of an engineering school were asked the starting annual salary for their first engineering job after graduation, and the sampling variability was low. if the average salary of one of the groups was $65,000, which of these is least likely to be the average salary of another of the groups? o a. $64,000 o b. $65,000 o c. $67,000 o d. $54,000