11. A psychologist wants to evaluate the effect of a new growth hormone on weight. It is known that regular adults (with no hormone) weigh an average of 400 grams with a population standard deviation of 15 grams. The psychologist gives 25 newborn rats an injection of the hormone and then measures their weights when they become adults. The sample mean for the 25 rats was 409 grams. Test at a significant level of .05. Use the 5 steps of hypothesis testing. Step 1: Restate the Questions as a Research Hypothesis Population 1: Population 2: Null Hypothesis: Research hypothesis: Step 2: Determine the characteristics of the comparison distribution (Draw your Comparison Dist.) Step 3: Determine the cutoff score (critical value) on the comparison distribution at which the null hypothesis should be rejected Step 4: Determine your sample's score on the comparison distribution Step 5: Decide whether to reject the null hypothesis Step 6: Calculate and Determine Effect Size