Answer:
Natural gas is non renewable energy.
Explanation:
Because they were formed from the buried reamains of plants and animals that live a million years ago. It is formed from fossil fuels.
Answer:
160 m
Explanation:
The intensity, I, of the sound is inversely proportional to the square of the distance, r, from the source.

Hence,


From the question,
is half of 



The answer is d. Wavelength
I'm not quite sure what happens to Fay so I didn't finish but hope it helps
Answer:
The initial velocity is 50 m/s.
(C) is correct option.
Explanation:
Given that,
Time = 10 sec
For first half,
We need to calculate the height
Using equation of motion

....(I)
For second half,
We need to calculate the time
Using equation of motion



Put the value of h from equation (I)


According to question,


Put the value of t₁ and t₂



Here, g = 10
The initial velocity is


Hence, The initial velocity is 50 m/s.