In the following equations, t represents time in hours and m represents mass in mg Which of them (if any) would have a mass less than 50 mg after 2 hours? Select all that apply a. y = 100(0.5)^x b. y = 500(0.3)^x C. y = 80(2)^x d y = 10(1.2)^x e. y = 30(1.5)^x f. y = 80(0.2)^x g. y = 100(2)^x