1.  Refer to Exercise 4. Assume that the cost of repairing an assembly whose clearance is too little is $2, and the cost of repairing an assembly whose clearance is too much is $3.

a.  Express the total cost of repairs in terms of X and Y.

b.  Find the mean of the total cost of repairs.

c.   Find the standard deviation of the total cost of repairs.

2.   Refer to Exercise 9.

a.  Find µX+Y

b.  . Find σX+Y .

c.   Find P(X + Y = 5)

3.  Refer to Exercise 9.

a.   Find the conditional probability mass function pY\X (y | 4)

b.   Find the conditional probability mass function pY\X (x | 3)

c.    Find the conditional expectation E(Y | X = 4).

d.  Find the conditional expectation E(X | Y = 3).