Need to breakdown of how the answer was determined, I am having trouble.

3. For each of the following events or transactions, identify the fund or funds that will be affected. 1) A city government provides electricity services to residents for a fee. 2) A printing shop was established to handle the printing needs of a county government. 3) A philanthropist donates $1 million for zoo maintenance, only earnings can be used. 4) A city government collects sales taxes on behalf of the state and for some of its counties and municipalities. 5) Interest is paid on a state government's general obligation bonds