It is A or D but I believe A
The correct answer to the question is : B) The weight of the water, and C) The height of the water.
EXPLANATION :
Before coming into any conclusion, first we have to understand potential energy of a body.
The potential energy of a body due to its position from ground is known as gravitational potential energy.
The gravitational potential energy is calculated as -
Potential energy P.E = mgh
Here, m is the mass of the body, and g is the acceleration due to gravity.
h stands for the height of the body from the ground.
We know that weight of a body is equal to the product of mass with acceleration due to gravity.
Hence, weight W = mg
Hence, potential energy is written as P.E = weight × height.
Hence, potential energy depends on the weight and height of the water.
Answer:
Absolute pressure of the oil will be 102822.8 Pa
Explanation:
We have given height h = 31 cm = 0.31 m
Acceleration due to gravity 
Specific gravity of oil = 0.600
So density of oil 
We know that absolute pressure is given by 
, here 
So absolute pressure will be equal to 
So absolute pressure of the oil will be 102822.8 Pa
It is indeed true that scientists have known about the background radiation (commonly known as the Cosmic Microwave Background) since the early 60s. It was first discovered quite by accident by Penzias and Wilson working at Bell Labs, who detected it as an unexplainable interference in their precision radio equipment. When people finally figured out exactly what it was they were seeing, they won the Nobel Prize for their discovery. Only a few years before, George Gamow had predicted that if the Big Bang theory were correct, we should observe just such a background radiation. The CMB is not the only evidence in favor of the Big Bang, but it is one of the most important. It is a natural consequence of the theory, and is pretty unexplainable in steady-state cosmology.
The 15-20 billion year number comes not from the CMB, but rather predominantly from measurements of nearby and distant galaxies, particularly their rates of expansion away from us. We find that the distance to a galaxy is proportional to its recessional velocity. The constant of proportionality is the Hubble Constant, H, which turns out to be (approximately) the reciprocal of the age of the universe. So we measure the age by measuring recessional velocities. T = 1/H is only true, however, if the universe is not significantly accelerating or decelerating its expansion rate. If the rate of expansion is rapidly accelerating, the universe may be older than 1/H = 15 billion years, give or take. Such an acceleration would be caused by a large value of the Cosmological Constant, a sort of anti-gravity force predicted by General Relativity. There is some evidence that this might be the case.
So finally, yes, the age of the universe, being based on the empirical determination of H, is based on the observed evidence.
The form of energy a violin produces is sound.
