For Joan's doctoral dissertation experiment, 15 wheelchair users were randomly assigned to three groups with 5 in each group. These participants navigated in virtual-reality settings. Group 1 participants were in the virtual-reality setting (a building) as wheelchair users. Group 2 participants were in the virtual-reality setting in a wheelchair pushed by a walking person. Group 3 participants walked without aid in the virtual-reality setting. Joan measured the time each participant needed to complete the navigation of the virtual-reality setting. What are the dependent and independent variables?
a. Independent = wheelchair use; dependent = virtual-reality condition
b. Independent = wheelchair use; dependent = time needed
c. Independent = time needed; dependent = virtual-reality condition
d. Independent = virtual-reality condition; dependent = time needed
Question 2
An experimenter studies the effect of type of music during practice on recall of word lists using rock background music for 20 subjects, classical music for 22 others, and country/western for another 25 . How many levels are there in the experiment?
a. 3 c. 20
b. 67 d. 1