Is y=19x-5 proportional

1mile equals approximately 1.6 kilometers. which best approximates the number of miles in 6 kilometers?

Sasha drank 8 bottles of water everyday for a week. how many bottles of water did she drink in total?

Every weekday, mr. jones bikes from his home to his job. sometimes he rides along two roads, the long route that is shown by the solid lines. other times, he takes the shortcut shown by the dashed line. how many fewer kilometers does mr. jones bike when he takes the shortcut instead of the long route?