14.71 [EX14-71] A sample of 32 students received the following grades on an exam.

41 42 48 46 50 54 51 42 51 50 45 42 32 45 43 56 55 47 45 51 60 44 57 57 47 28 41 42 54 48 47 32

a. Does this sample show that the median score for the exam differs from 50? Use   0.05.

b. Does this sample show that the median score for the exam is less than 50? Use   0.05.