Answer: A 40 feet
Explanation:
If a building is 380 feet tall and the elevator has to descend 420 feet to get to the underground parking garage. So 420 - 380 to remove the height of the building from the equation. This would give us 40 feet underground left until the elevator reaches its desired destination.
The cable should be 50 feet.
If you draw the picture, you will see that you have a right triangle.
Let's just use the Pythagorean Theorem to find the hypotenuse (or cable).
30^2 + 40^2 = c^2
2500 = c^2
50 = c
Please excuse my sloppy writing but the answer is 30
