Mark Hirst, a high school student in Sydney, Australia, developed an innovatively shaped surfboard that radically increased the number of maneuvers a surfer could perform in low surf. In his enthusiasm to research the market, he developed a comprehensive seven-page questionnaire to be completed by customers and distributed it among surf supply stores.
a. How will the length of the questionnaire affect the response rate?
b. What possible biases could arise from Mark's sampling method?