I need step by step instructions on how to compute the answers please.

A psychologist has prepared an "Optimism Test" that is administered yearly to graduating college seniors. The test measures how each graduating class feels about its future - the higher the score, the more optimistic the class. Last year's class had a mean score of 15. A sample of 9 seniors from this year's class was selected and tested. The scores for these seniors are 7, 12, 11, 15, 7, 8, 15, 9, and 6, which produce a sample mean of 10 and a SS = 94 (Gravetter et al., 2018). 1. On the basis of this sample, can the psychologist conclude that this year's class has a different level of optimism than last year's class? Note that this hypothesis test will need at statistic because the population variance is not known. 2. Calculate Cohen's d for this data. Please report your findings in APA style. To examine the strength of the vertical-horizontal illusion, a researcher prepared an example in which both lines were exactly 10 inches long. The example was shown to individual participants who were told that the horizontal line was 10 inches long and then were asked to estimate the length of the vertical line. For a sample of n = 25 participants, the average estimate was M = 12.2 inches with a standard deviation of s = 100 (Gravetter et al., 2018) 3. Use a one-tailed hypothesis test with alpha = .01 to demonstrate that the individuals in the sample significantly overestimate the true length of the line. 4. Calculate the estimated Cohen's d to measure the effect size. 5. Construct a 95% confidence interval for the population mean estimated length of the vertical line. A psychologist has prepared an "Optimism Test" that is administered yearly to graduating college seniors. The test measures how each graduating class feels about its future - the higher the score, the more optimistic the class. Last year's class had a mean score of 15. A sample of 9 seniors from this year's class was selected and tested. The scores for these seniors are 7, 12, 11, 15, 7, 8, 15, 9, and 6, which produce a sample mean of 10 and a SS = 94 (Gravetter et al., 2018). 1. On the basis of this sample, can the psychologist conclude that this year's class has a different level of optimism than last year's class? Note that this hypothesis test will need at statistic because the population variance is not known. 2. Calculate Cohen's d for this data. Please report your findings in APA style. To examine the strength of the vertical-horizontal illusion, a researcher prepared an example in which both lines were exactly 10 inches long. The example was shown to individual participants who were told that the horizontal line was 10 inches long and then were asked to estimate the length of the vertical line. For a sample of n = 25 participants, the average estimate was M = 12.2 inches with a standard deviation of s = 100 (Gravetter et al., 2018) 3. Use a one-tailed hypothesis test with alpha = .01 to demonstrate that the individuals in the sample significantly overestimate the true length of the line. 4. Calculate the estimated Cohen's d to measure the effect size. 5. Construct a 95% confidence interval for the population mean estimated length of the vertical line