A statistics instructor is interested in whether doing practice problems helps students tochangetheir grade on their statistics test.He gets a sample of n = 16 students in a statistics class and gives them a test before they any practice problems. He then makes them do practice problems and gives the same sample of students another test.The average differencebetween the two test scores in M_D= 7.84. The SS of the difference (SS_D) is 400.

Perform a repeated-measurest-test to determine whether doing practice problems helps students tochangetheir grade on their statistics test by stating or calculating the following:(Show your work or explain your answers for each!)

a. The null (H₀) and alternative (H_A) hypotheses. (4 points)

b. Whether we are using a one- or two-tailed test and why. (4 points)

c. Degrees of freedom (df) (3 points)

d. The critical/cut-offtstatistic using your degrees of freedom from the last step witha= .05. (4 points)

e. Sample variance (s_D²) (4 points)

f. Estimated standard error (s_MD) (4 points)

g.t-statistic (4 points)

h. Based on our t-statistic and our critical t, are we rejecting or failing to reject the null hypothesis? What does that mean for our research question?(4 points)