State whether the investigator should use independent samples, repeated measures, or matched samples:

a. An investigator wants to know whether children from different socioeconomic levels differ in the age at which they learn to skip. She gathers information about children’s socioeconomic levels and the ages at which they were first able to skip.

b. An investigator wants to know whether students with asthma participate in more or fewer college sports than students who do not have asthma. She gathers information about the presence or absence of asthma in the students studied, as well as the number of college sports in which those students’ parents participated while young (to control for family pressure to play sports).