Answer:
Step-by-step explanation:
Think: 2/5 its body weight in 1/2 hour immediately becomes 4/5 its body weight in 1 hour. There's a proportional relationship here.
X equals POSITIVE one. so 63 minus one equals 62. the answer is a
We know that the balloon ascends at the same constant rate, that means that after the penny drop is:

this comes from the fact that the initial height is 500 ft and that for each second the balloon ascends 10 feet.
9,000,000 = 9×10^6
9×10^6/1×10^6 = 9
There are 9 square megameters in 9,000,000km