An airplane flies at an altitude of 14,690 feet while a submarine is submerged at a depth of 521 feet below the surface of the ocean. What is the difference between these two elevations?

15,211 feet

Step-by-step explanation:

According to the question,  given data are as follows:

Airplane altitude = 14,690 feet above

Submarine depth = 521 feet below

So, let the difference between these two elevation be d,

So, we can calculate difference by using following formula:

Difference = Airplane altitude + Submarine depth

By putting the value, we get

Difference = 14,690 + 521

= 15,211 feet

a) justify

step-by-step explanation:

justifying is just part of everyday life. justify kind of means proof so i think the answer is a) justify.