The manager of a shopping mall wishes to expand the number of shops available in the food court. She has a market researcher survey the first 110 customers who come into the food court during weekend afternoons to determine what types of food the shoppers would like to see added to the food court. The survey has bias. What is the cause of the bias?

A. Nonresponse

B. Response bias

C. Sampling bias

Referring to the information in the previous question, suggest a remedy to the problem.

A. Reword the question so that is balanced.
B. Increase the sample size so that more people respond to the question.
C. Ask customers throughout the day on both weekdays and weekends.

An annual marathon covers a route that has a distance of approximately 26 miles. winning times for this marathon are all over 2 hours. the following data are the minutes over 2 hours for the winning male runners over two periods of 20 years each. earlier period 14 12 15 22 13 10 19 13 9 14 20 18 16 20 23 12 18 17 6 13 recent period 7 11 7 14 8 9 11 14 8 7 9 8 7 9 9 9 9 8 10 8 (a) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the earlier period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks. for more details, view how to split a stem.) minutes beyond 2 hours earlier period 0 1 2 (b) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the recent period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks.) minutes beyond 2 hours recent period (c) compare the two distributions. how many times under 15 minutes are in each distribution