28: A proton has a charge of positive one and an electron has a charge of negative one. An ion contains 7 protons and 9 electrons. What is the overall charge of the ion?
29: A golf team has 5 golfers. Three of the team's players each have a -4 on their rounds for the day and the remaining players each have a -3 on their rounds. What is the team's total score?
30: Brianna withdrew $1,695 from her account through an ATM machine. Before the transaction, she had a balance of $3523.12 in her account. What is her balance now?