15.The median score for the class is

　　A.76

　　B.77

　　C.78

　　D.79

　　E.80

　　答案：B

　　16.If 5 points were added to each score, which of the following would not be affected?

　　A.The highest score

　　B.The mean for all scores

　　C.The median for the seniors'scores

　　D.The mode for the juniors' scores

　　E.The standard deviation for all scores

　　答案：E

　　17.If the mean score for the juniors were known, which of the following could be calculated from the information given?

　　(1) The range of the scores for the seniors

　　(2) The median score for the juniors

　　(3) The mean score for the seniors

　　A.None

　　B.(1) only

　　C.(3) only

　　D.(1) and (2)

　　E.(2) and (3)

　　答案：C