1) What happens to the variance of a set of scores if

(a) A constant a is added to each score in the set?

(b) A constant a is subtracted from each score in the set?

(c) Each score is multiplied by a constant a?

(d) Each score is divided by a constant a?

2) Suppose the midterm grades for 10 students are the following: 70, 65, 75, 80, 63, 90, 71, 75, 93, 83. Using R, show what happens to the standard deviation of the grades if each of the following happens. Attach R code.

(a) The teacher added 5 marks to everyone's grades.

(b) The teacher subtracted 5 marks from everyone's grades.

(c) The teacher multiplied everyone's grades by 5.

(d) The teacher divided everyone's grades by 5

3)What happens to the standard deviation of a set of scores if

(a) A constant a is added to each score in the set?

(b) A constant a is subtracted from each score in the set?

(c) Each score is multiplied by a constant a?

(d) Each score is divided by a constant a?