For part (a), to find AB = length, I need to know h and plug and chug. Correct?
For part (b), once I find the length AB from part (a), I would then simply plug and chug. Correct?
For part (c), you found the height to be 53.02 feet. If I wanted to find the height from the height of the balloon to ground level, I would then simply add 20 feet to 53.02 feet. Correct?