a- for an exam given to a clas, the students scores ranged from 35 to 98, with a mean of 74. whichof the following is the most realistic value for the standard deviation:-10, 1,12,60? clearly explain what is unrealistic about the other values
b- the sample mean for the date set equals 80. whichof the following is an impossible value of the standard deviation? 200,0,-20? why?