To study the effect of stimulus type on memory recall, Hayden had participants receive either an auditory or visual presentation of a poem. After the presentation, participants were asked to answer several questions about the poem. Which experimental design did Hayden use?

Hayden used posttest-only research design.

Explanation:

The posttest-only control group design is a method used in research design where a test is given to the students after an instructional program is completed. It is normally used in conjunction with a pretest which helps identifying the effectiveness of the program

the median of the data is 4.

step-by-step explanation:

the median means the middle number of a given number.

to decide which one is the median, arrange in ascending or descending order. but sometimes, you may find two(2) number in the middle, but it's easy, just add them together and divide by 2.

so,   determine the median of the data. 2, 3, 3, 4, 5, 7, 9

it is already arranged, count 3 times forward and 3 backward and the one left is your answer.

2,3,3,4,5,7,9

our answer is 4.

hope this !

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