Thank you for the *delete me*
I've read all the rules, but I continue to make mistakes.
I've tried about 5 times, using different perspectives, but I get the same solution
The S atom in CuSO4 S= 6+
The N atom in HNO2 N = 3+
The Na atom in Na2SO4 Na = 5+
The Cu atom in CuSO4 Cu = 2 +