15. What is the value of the rational expression when x = 12 A. 2 B. 3 C.4 D.5 16. When is a rational algebraic expression in lowest term? A. If the numerator and denominator are both of degree one. B. If either the numerator or the denominator is factored completely. C. If the numerator and denominator have no common factor other than 1. D. If the numerator and denominator have no common factor other than -1. flow furathalavracions