What is the calculation for 70 increased by 9%

Given the function f(x) = 3x + 1, evaluate f(a + 1). a. 3a + 1 b. a + 2 c. 3a + 4

An advertising firm has an old computer that can prepare a whole mailing in 6 hours. with the of newer model the job is complete in 2 hours. how long would it take the newer model to do the job alone?

Julie goes to the sports store and spends $40.50 before tax. she buys a pair of shorts for $21.75 and 3 pairs of socks that each cost the same amount. how much does each pair of socks cost? $$