The one that both benefits each other is the one I think it's mutalistic
Answer:
Uhhhhh? can u explains? lol
Electrical forces travel far through the universe
Answer:

Explanation:
When an object goes on a circular movement, it has a centripetal acceleration that always points toward the center of the circle, it is the responsible of the change of direction in the movement of the object. and that centripetal acceleration is related with the speed in the next way:
, with v the speed, r the radius of the track that is half of the diameter (22.5 m)


Answer:B
Explanation:
Option A:
In the nuclear reactions,neutron can be split into proton an electron.
In this case,the number of protons are increasing,increasing the atomic number.
Hence,the atomic number is not conserved.
Option B:
In any reaction the sum of number of neutrons and number of protons remain constant before and after the reaction.
Option C:
The mass number may change for the atoms.For example
emission reduces the atomic number by 
Option D:
In the nuclear reactions,neutron can be split into proton an electron.
So,they number of neutrons may change.