1. At the certain university, average cost of books per student was 400.00 last semester. In the sample of 40 students this semsester, their average cost was 340.00 with standard deviation of 80.00. Dean of students thinks that costs are greater this semester. Determine the test value for this hypothesis

A) 15.00
B) 2.37
C) 0.38
D) 0.75

2. Medical researcher is interested in whether patient's left arms or right arms are longer. if 14 patients participate in this study (so that n left arms and n right arms are estimated), how many degrees of freedom must researcher use in her t-test critical value suppose that variances are equal?

A) 13
B) 27
C) 14
D)26