If oxygen has 6 valence electrons, predict the charges on a monatomic oxygen ion.
A) +6
B) -6
C) +2
D) -2

I'm at a bookstore with $\$35$ in my pocket and a $20\%$-off coupon. what is the cost of the most expensive book i can buy with my money and the coupon? (assume that there are books of every possible price in the bookstore. it's a large bookstore! )