[tex]y=c(a)^x\\\\if\ a > 0\ then\ "Growth"\\\\if\ 0 < a < 1\ then\ "Decay"\\-----------------------------\\y=200(0.5)^{2t}\to a=0.5 < 1-"Decay"\\\\y=\dfrac{1}{2}(2.5)^{\frac{t}{6}}\to a=2.5 > 1-"Growth"\\\\y=(0.65)^{\frac{t}{4}}\to a=0.65 < 1-"Decay"[/tex]
