Answer:
1. CaCO3 + 2HCl —> CaCl2 + H2O + CO2
2. Mg(OH)2 + 2HCl —> MgCl2 + 2H2O
3. Na2CO3 + 2HCl —> 2NaCl + H2O + CO2
A.
An amine refers to a nitrogen-based compound. Since A is the only option with nitrogen, that would be the answer.
The greenhouse effect captures the sun's energy and keeps the earth warm.