Answer:
i think it would be B. Aluminum, Al and D. Boron, B
Explanation:
since they're both in group 13 and they forms a 3+ ion
By unplugging unused devices, by turning off any unused lights, and by switching your lightbulbs to something more energy efficient.
They would be an expert in astronomy
astronomy:the branch of science that deals with celestial objects
I really doubt because the universe is supposed to be infinite