ok so this was really confusing, but i think i know the answer. D. ...hairy and ancient hermit crabs and swift, darting minnows and sometimes a
crumbling sand dollar.
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)
$\mathrm{CuCO_3+ 2HNO_3}\rightarrow \mathrm{Cu(NO_3)_2+ CO_2+ H_2O}$
Answer:
atomic number
Explanation:
atomic number is the number of protons