PLEASE HELP!
Bob's Bricks has determined that a brick measuring 5 inches long has a z-score of +1 and a brick measuring 5.75 inches long has a z-score of +2.

What is the mean length of the bricks produced at Bob's Bricks?

A.4.00 inches
B. 4.25 inches
C. 4.75 inches
D. 5.25 inches