It is because the weight is equal to each other and balances out. example war ships have tons of metal, but it spreads the weight on the water
In simpler terms, a proton and neutron weigh 1 amu (atomic mass unit) each.
The nucleus has 15 protons and 18 neutrons. Since a proton's and a neutron's weight is only 1 amu, we can simply add the number of protons and neutrons to find the total mass of the nucleus:

The nucleus' mass is 33 amu.
Answer:
A,B,C,D the answer is { }
D) Pitch since it does not measure distance, media, or speed (because it only has one speed)