The function f(h)=m(1/2)^h gives the mass, m, of a radioactive substance remaining after h half-lives. iron has a half-life of 2.7 years. which equation gives the mass of a 200 mg iron sample remaining after y years, and approximately how many milligrams remain after 12 years? a) f(x) = 2.7(0.5)200; 1.7 mgb) f(x) = 200(0.5)12; 30.8 mgc )f(x) = 200(0.5)12; 30.8 mgd) f(x) = 200(0.185)12; 3.2 mg  e)f(x) = 200(0.774)12; 9.2 mg