1. A researcher wants to test the effect of music on memory

performance. He randomly assigns participants to one of

three conditions: listening to classical music, listening to

rock music, or listening to no music while studying a list of

words. He then measures how many words they can recall

after a 10-minute delay. What is the independent variable

in this experiment?

a) The type of music

b) The number of words

c) The memory performance

d) The 10-minute delay

*Answer: a) The type of music

Rationale: The independent variable is the factor that the

researcher manipulates or varies to see if it has an effect on

the dependent variable. In this case, the type of music is the

independent variable.*

2. A researcher wants to test the effect of caffeine on

alertness. She measures the alertness level of 100

participants before and after they drink either a cup of

coffee or a cup of decaffeinated coffee. She then compares

the alertness levels between the two groups. What is the

research design in this experiment?

a) Between-subjects design

b) Within-subjects design

c) Quasi-experimental design

d) Correlational design

*Answer: a) Between-subjects design