Answer:
The new navigation height of the submarine is -62.25 feet.
Explanation:
Given that a submarine travels at an elevation of -75 3/4 ft relative to sea level, and then its elevation changes by -16 3/8 ft, to determine what is the new elevation of the submarine the following calculation must be performed:
3/4 ft = 0.75 ft
-75 x 0.75 = -56.25 ft
3/8 ft = 0.375 ft
-16 x 0.375 = -6 ft
-56.25 + -6 = -62.25
Thus, the new navigation height of the submarine is -62.25 feet.