a
\(Cu+2AgNO_3\rightarrow Cu\left(NO_3\right)_2+2Ag\downarrow\)
0,05 --> 0,1-----------> 0,05------>0,1
b
\(n_{Cu}=\dfrac{3,2}{64}=0,05\left(mol\right)\)
\(m_{Cu\left(NO_3\right)_2}=0,05.188=9,4\left(g\right)\)
c
\(a=m_{Ag}=108.0,1=10,8\left(g\right)\)
d
\(V_{AgNO_3}=\dfrac{0,1}{0,5}=0,2\left(l\right)\)