A researcher provides10children$100each and another10children$20each. She tracks how they decide to spend the money. Which statement best describes the type of study the researcher is doing?

a. an observational study that is not a statistical study

b. an experimental study that is not a statistical study

c. an observational study that is a statistical study

d. an experimental study that is a statistical study

There are105players on a local college's football team. Which phrase describes the students on the football team?

a. the population of men in college

b. a sample of students in the college

c. the population of college athletes

d. a sample of bicyclists in the college

An email is sent to everyone at a school, encouraging students to participate in a school-wide survey for the chance to win a pair of concert tickets.

A sample created from this method may suffer from which of these biases?

a. social desirability bias

b. self-selection bias

c. none

d. area bias