Answer:
810 feet.
Explanation:
We are supposed to find the final altitude of the helicopter.
We have been given that a helicopter is flying at a altitude of 785 feet, this means that altitude of helicopter is positive.
Further, the helicopter descends 570 feet, this means that altitude of helicopter is
.
Finally, the helicopter ascends 595 feet, this means that altitude of helicopter is
.


Therefore, the final elevation of helicopter is 810 feet.