15 * 28 = 420. Should be your answer.
Answer:
19.8494332413? Sorry I couldn't be more helpful.
Step-by-step explanation:
Use the Pythagorean theorem.

A = s^2
A = 40
40 = s^2...by taking the square root of both sides, u eliminate the ^2
sqrt 40 = s
6.32 = s <===
Starts at 1,000feet
Each second is getting 20 feet closer to the surface since is ascending ( going higher)
1,000/20= 100/2=50 second it takes to reach the surface
Answer:
last one
Step-by-step explanation: 25 divided by four is 6.25