The following table gives joint probabilities relating cell phone usage to stopping properly at intersections.
a. Compute the probability of failing to stop at an intersection, given the driver was on the cell phone.
b. Compute the probability of failing to stop at an intersection, given the driver was not using a cell phone.
c. Compute the probability of stopping properly at an intersection, given the driver was on the cell phone.
d. Are cell phone usage and failing to stop at intersections independent of each other? Why or why not?

Failed to stop at intersection Stopped at intersection On cell phone Not using cell phone 0.047 0.201 0.016 0.736