A sample is selected from a population with 50 After a trea

A sample is selected from a population with = 50. After a treatment is administered to the individuals in the sample, the mean is found to be M = 55 and the variance is s² = 64.

a. If the sample has n = 4 scores, then conduct a hypothesis test to evaluate the significance of the treatment effect and calculate Cohen\'s d to measure the size of the treatment effect. Use a two-tailed test with a = .05.

b. If the sample has n = 16 scores, then conduct a hypothesis test to evaluate the significance of the treatment effect and calculate Cohen\'s d to measure the size of the treatment effect. Use a two-tailed test with a = .05.

c. Describe how increasing the size of the sample affects the likelihood of rejecting the null hypothesis and the measure of effect size.

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