Final answer:
The average rate of elevation change for the diver is -2 feet per second, calculated by dividing the change in elevation, -50 feet, by the time, 25 seconds.
Step-by-step explanation:
The question asks for the average rate of elevation change for a scuba diver who descended from 0 feet to -50 feet in 25 seconds. To calculate this, you would take the change in elevation, which is -50 feet (since the diver is going down, this is a negative change), and divide it by the time it took, which is 25 seconds. The calculation is -50 feet ÷ 25 seconds = -2 feet per second. Therefore, the integer that represents the diver's average rate of elevation change is -2 feet per second.