Answer:
The mass number of an atom is its total number of protons and neutrons. Atoms of different elements usually have different mass numbers , but they can be the same. For example, the mass number of argon atoms and calcium atoms can both be 40.
Explanation:
It is bacteria just took the test
Answer:
most likely the water was evaporated by the sun
Explanation: Evaporation is the process in the water cycle when water particles heat up and turn from a liquid into a gas.
