Answer:
Natural gas, emitting fewer harmful chemicals into the atmosphere than other fossil fuels, can help to mitigate some of these environmental issues. These issues include: Greenhouse Gas Emissions. Smog, Air Quality and Acid Rain
Explanation:
a)
A: Copper
B: CuO
C: 
D: $\mathrm{CuCO_3}$
E: $\mathrm{CO_2}$
F: $\mathrm{Cu(NO_3)_2}$
b)
$\mathrm{CuO+ H_2SO_4}\rightarrow \mathrm{CuSO_4 + H_2O}$
c)
$\mathrm{CuCO_3+ 2HNO_3}\rightarrow \mathrm{Cu(NO_3)_2+ CO_2+ H_2O}$
<span>Why are leaves different colors?</span><span>
The chlorophyll breaks down</span>