A nine-year-old tested professional touch therapist. Using a cardboard partition, she held a hand above one of the therapist’s hands and the therapist was asked to identify the hand that was chosen. What type of study is this? What are the variables of interest?

a. Experiment. The variable of interest is the result of either correct or incorrect to each trial.

b. Observational study. The valuable of interest is which hand is chosen by the therapist for each trail.

c. Observational study. The variable of interest is the result of either correct or incorrect to each trial.

d. Experiment. The valuable of interest is which hand is chosen by the therapist for each trail.

c.Observational study. The variable of interest is the result of either correct or incorrect to each trial.

Step-by-step explanation:

Observational study is the type of study when a researcher don't influence the outcome of an experiment by imposing a treatment and only observe the outcome of an experiment. A nine year old tested professional observes therapists choices and so this is the observational study.

A nine year old tested professional observes therapists choices and the choice of therapist can be correct or incorrect. So, the variable of interest is the result of either correct or incorrect to each trial.    

answer: 48

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