Answer:
Explanation:
Given
mass of archer 
Average force 
extension in arrow 
Work done to stretch the bow with arrow


This work done is converted into kinetic Energy of arrow

where v= velocity of arrow



(b)if arrow is thrown vertically upward then this energy is converted to Potential energy




Answer: 
Explanation:
Given
mass of ball m=10 kg
It is placed at a height of 150 m
It is dropped from the height and allowed to free fall for 40 m
Velocity acquired by the ball during this fall is given by 
Insert u=0, a=g

Kinetic energy at this instant

Answer- Helium
You can by the number of protons, and if you look at a periodic table the atomic number of helium is the same as the number of protons
The photosynthesis equation is :
H2O + CO2 + sunlight (energy) > C6H12O6 + O2
So water (H2O) and carbon dioxide (CO2) are the raw materials need for photosynthesis.