The two are potassium and rubidium. Why? Na is an alkali metal. As you go down the metals become more reactive.
Calcium has 20 protons. Why? The atomic # is 20 (the one at the top).
It has 20 neutrons. Why? The atomic mass (the number on the bottom) is ~40, ignoring electron mass. 40- 20 protons = 20 neutrons.
It has 20 electrons.
Why? The # of protons and electrons is the same. Ions aren't on the periodic table.
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The mitochondria converts food into energy
Refers to the environmental capacity , as much of something it can hold
Answer:
I think the answer is B i might be mistaken though c:
Explanation:
There would be dead animals overloading the Earth. Think about it, without worms and other things that break down dead things they would still be here and just sit there.
