Discuss whether the below transactions are income to Angelo who is a coffee salesman, citing at least one case or section for each answer: 

1. His base wage of $45,000.

2. Commissions paid to him by his employer because he met his targets. 

3. Commissions paid to him by his suppliers. He does not declare this commission to his employer. 

4. Cash work he does on the side, as an unregistered tax agent where he charges $50 a tax return.