Given independent randomvariables, X andY, with means and standard deviations asshown, find the mean and standard deviation of each of the variables in parts a to d.

a) X21

b) 0.4Y

c) X+Y

d) XY

Mean SD

X 70 14

Y 12 4

a) Find the mean and standard deviation for the random variable X21.

E(X21)=

SD(X21)=

b) Find the mean and standard deviation for the random variable 0.4Y.

E(0.4Y)=

SD(0.4Y)=

c) Find the mean and standard deviation for the random variable X+Y.

E(X+Y)=

SD(X+Y)=

d) Find the mean and standard deviation for the random variable XY.

E(XY)=

SD(XY)=

PLEASE SHOW HOW TO GET THE SD FOR EACH PROBLEM. THANK YOU!