There is only one answer out of those three PLEASE HELP ME I'M FALLING IN MATH CLASS, PLEASE HELP ME! (no link's please)

Colby and jaquan are growing bacteria in an experiment in a laboratory. colby starts with 50 bacteria in his culture and the number of bacteria doubles every 2 hours. jaquan starts with 80 of a different type of bacteria that doubles every 3 hours. let x equal number of days. colbys experiment follows the model: a.) y=50*2^x b.) y=50*2^8x c.) y=50*2^12x jaquans experiment follows the model: a.)80*2^x b.)80*2^8x c.)80*2^12x

Which expression gives you the distance between the points (5,1)and(9,-6)

Atransformation t : (x,y) (x-5,y +3) the image of a(2,-1) is