<span>the gravational potential energy of anything on the ground is zero. When calculating potential energy you take height in meters and multiply it by the mass of the object in kilograms and the acceleration of gravity to get a new unit called Joules.
Any object at ground level has a potential energy of zero newtons becuase anything multiplied by zero is zero. An object with mass of 54 kg, 4 meters above the ground has a gravitatinal potential energy of 2116.8 Joules.</span>
I believe the answer is D. <span>The hypothesis is revised and another experiment is conducted.</span>
Answer:
it appears to be farther away than it actually is, and therefore smaller then the object itself.
Taking into account the rule of three for the change of units, the mass of the book is 45600 miligrams.
First of all, the rule of three is a mathematical tool that helps you quickly solve proportionality problems.
Having three known values and one unknown, a proportional relationship is established between all of them in order to find the fourth term of the proportion.
If the relationship between the magnitudes is direct (when one magnitude increases, so does the other; or when one magnitude decreases, so does the other), the rule of three is applied as follows, where a, b and c are known values and x is the unknown to calculate:
a → b
c → x
So: 
Being 1 kg equivalent to 1000000 milligrams, In this case the rule of three is applied as follows: if 1 kg equals 1000000 milligrams, 4.56×10⁻² kg equals how many milligrams?
1 kg → 1000000 milligrams
4.56×10⁻² kg → x
So:

<u><em>x=45600 miligrams</em></u>
In summary, the mass of the book is 45600 miligrams.
Learn more:
Answer:
ξ = 0.00845020162 V or 8.4 mV
Explanation:
Magnetic flux measures the total magnetic field that passes through a known area. Magnetic flux describe the effect of magnetic field in a given area. Mathematically,
magnetic flux (Ф) = BA cos ∅
where
A = test area
B = magnetic field
before the flip
Ф = Bπr²N
N = number of turn
magnitude of induced emf = N |ΔФ/Δt|
ξ = 2Nπr²B/dt
ξ = 2 × 22 × π × (1.02/2)² × 0.000047/0.2
ξ = 44 × π × 0.51² × 0.000047/0.2
ξ = 44 × π × 0.2601 × 0.000047/0.2
ξ = 0.0005378868 × 3.142/0.2
ξ = 0.00169004032/0.2
ξ = 0.00845020162 V or 8.4 mV