If all the natural numbers between 1 and 20 are multiplied by 3, then what is the variance of the resulting series?

If all the natural numbers between 1 and 20 are multiplied by 3, then

1.	If all the natural numbers between 1 and 20 are multiplied by 3, then what is the variance of the resulting series?
A.	99.75
B.	199.75
C.	299.25
D.	399.25
Answer» D. 399.25