Here are the answers to the question. Make sure to give a valid reason, please.
A. the sum of the protons and neutrons in one atom of the element.
B. a ratio based on the mass of a carbon-12 atom.
C. a weighted average of the masses of an element's isotopes.
D. twice the number of protons in one atom of the element.
It is simply called Entropy.
It's either A or B because it starts off as nuclear energy.
Given the time, the final velocity and the acceleration, we can calculate the initial velocity using the kinematic equation A:

A skateboarder flies horizontally off a cement planter. After a time of 3 seconds (Δt), he lands with a final velocity (v) of −4.5 m/s. Assuming the acceleration is -9.8 m/s² (a), we can calculate the initial velocity of the skateboarder (v₀) using the kinematic equation A.

Given the time, the final velocity and the acceleration, we can calculate the initial velocity using the kinematic equation A:

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