Answer:
-7 feet
Step-by-step explanation:
The total distance the diver rose is 5*15 = 75 feet
If we take the zero at the water surface, then the initial position, that is, 82 feet below the surface has to be considered as -82. The 75 feet risen by the diver is a positive quantity, then his new position, in relation to the water surface, is -82 + 75 = -7 feet, i. e. 7 feet below the surface.