An attendant collected 45 coins from a parking meter. the value of the coins was $7.25, and there were 5 more quarters than nickels. which system models this situation?

a.) n+5=q and .05n +.25q=7.25
b.) q+5=n and .05n +.25q=7.25
c.) n+5=q and n+q=7.25
d.) n+5=q and 5n+2q=7.25