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)
$\mathrm{CuCO_3+ 2HNO_3}\rightarrow \mathrm{Cu(NO_3)_2+ CO_2+ H_2O}$
1 ba+2 br——>1 babr2
u just have to make sure u have the same number of each type of atom on either side of the equation:)
Answer:
I think the answer is boiling
It's reported inside the riddles or decorations