ABC Bookstore sells new books, n, for $12, and used books, u, for $8; and magazine,m,for $5 each. the store sold 5 more used books than new books, and twice as many magazines, new books, and old books did ABC bookstore sell?
A. n=12; u=14;m=7
B.n=12;u=8;m=5
C.n=14,u=12;m=7
D.n=7;u=12;m=14