Answer:
He could have many different hypothesis, but here is one.
Explanation:
If rubber bands are wider, then the rubber bands will stretch further, because the wider a rubber band is the stronger it is.
Answer:
The average power the student expended to overcome gravity is 560W, Watts is a units of work it is Joules /time or kg*
/ 
Explanation:
Weight = 700N

The power is the work in (Joules) or (N*m) in a determinate time (s) to get Watts (W) units for work

Answer:
Photosynthesis
Explanation:
It removes carbon naturally.
Answer:
1.0 x 10^-3 m
Explanation:
1mm = (1/1000) m = 0.001m = 1.0 x 10^-3m (because to get 1.0, you have to movi the decimal point in the "0.001" three spots over to the right)
Yes it is a chemical reaction