HELP!!

the question is in the picture. i just need question c answered:)

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

The pair of coordinates that do not represent the point( 5,150’) is a. (5,-210) b. (5,210) c. (-5,330) d. (-5,-30)

Ihave 9 cowry shells if a dozen eggs(12 eggs) cost 2 cowry shells how many dozens can i purchase