A researcher is interested in understanding whether the mean time to complete a four-year college degree varies based on gender. She draws a sample of 12 college graduates6 men and 6 women, and asks them how many years they took to finish their degree. Assuming that the data are drawn from a normal distribution, test the null hypothesis of no difference in mean years to degree competition between men and women:

Men Women 4 5 4 6 4 4 6 7 4 5 5 3

a1. Find the mean for men? [A1] a2. Find the mean for women? [A2] b1. Find the variance for men [B1] b2. Find the variance for women [B2] c. Find the standard error of the differences between means [C] d1. compute the t ratio [D1] d2. What is the degree of freedom [D2] d3. what is the critical value? [D3] e. Retain the null hypothesis at? [E]