80, -160, 320, -640,....    *-2      *-2    *-2  r = -2 -640 * -2 = 1280 1280 * -2 = -2560 -2560 * -2 = 5120 Option 2 y = 4 * 2^x when x = -6 y = 4 * 2^(-6) y = 4*(1/2^6) y = 4*(1/64) y = (4/64) y = 1/16 Option 3