Answer: A) -818 feet
Step-by-step explanation:
Given : A submarine's position is 600 feet below sea level. It descends 218 feet.
Integers , we use negative (-) signs to represent below and descend .
Thus , in terms of integers
Initial position of submarine 600 feet below sea level= -600 feet
After descends 218 feet, the submarine's new elevation =
-600+(-218) feet
= -600-218 feet [(+)(-)=(-)]
= -(600+218) feet = -818 feet [-a-b=-(a+b)]
Hence, the submarine's new elevation = -818 feet