Answer:
Water is a human necessity. Therefore, it is one of the first things a human settlement would need to have. A community cannot thrive without a water source.
Answer:
A
Explanation:
A chemical change is when a new substance is created, which often has its own chemical properties, so A is the correct answer.
Neither of them are used in magnets they don’t attract metal
Answer: See below
Explanation: a. The mass of an element is composed of:
protons: 1 amu each
neutrons: 1 amu each
electrons: 0 amu each
Only the protons and neutrons are counted in the atomic mass of an element
b. Electrons are assigned a mass of 0. They do have a mass, but it is exceedingly small compared to the protons and neutrons, so they are left out of the calculation of an element's mass.
c. An element becomes unstable if the neutrons exceed the protons by a certain ratio, dependent on the element.
