Answer:
petroleum
Explanation:
Petroleum is a gas that we use that just goes into the air whilst water can be recycled and purified, wind never ever goes away, and solar power can be converted into energy.
Answer:
Number of photons travel through pin hole=
Explanation:
First we will calculate the energy of single photon using below formula:

Where :
h is plank's constant with value 
c is the speed of light whch is
λ is the wave length = 532nm

E=
J
Number of photons emitted per second:

Number of photons emitted per second=
=
Where:
A-hole is area of hole
A-beam is area of beam
d-hole is diameter of hole
d-beam is diameter if beam
=
=
=
Number of photons travel through pin hole=
Number of photons travel through pin hole=
Answer:
A heavy ball of demolition machine is storing energy when it is held at an elevated position .
Answer:
hope this helps
Explanation:
The elements in the modern periodic table are arranged in order of their atomic numbers, which is the number of protons in the nuclei of the atoms of a an element. Each element has a unique atomic number. The atomic numbers are also whole numbers.