You are bicycling along a straight north-south road. Let the x -axis point north. Describe your motion in each of the following cases. Example: ax > 0 and vx > 0 means you are moving north and speeding up.
(a) ax > 0 and vx < 0.
(b) ax = 0 and vx < 0.
(c) ax < 0 and vx = 0.
(d) ax < 0 and vx < 0.
(e) Based on your answers, explain why it is not a good idea to use the expression "negative acceleration" to mean slowing down.