Question

a scientist uses a submarine to study ocean life. she begins at sea level, which is an elevation of 0 feet. she descends 26.4 feet. she then rises 21.9 feet. next, she descends a second time, 58.3 feet. how many feet must she now rise to get back to sea level?

Explanation:

Step1: Calculate the net descent after the first two - stage movement

The initial descent is 26.4 feet and then a rise of 21.9 feet. The net descent after these two steps is $26.4 - 21.9=4.5$ feet.

Step2: Calculate the total descent after the second - stage descent

After the second descent of 58.3 feet, the total descent is $4.5+58.3 = 62.8$ feet.

Answer:

62.8