Answer:
D, what do people need to be happy
Explanation:
first we need to understand what positive psychology means. Positive Psychology according to Wikipedia can be defined as <em>the scientific study of the "good life", or the positive aspects of the human experience that make life worth living. </em>
Therefore the correct option is D
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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