a. you are the only driver that is experiencing a negative externality from the heavy traffic
b. the opportunity cost of idling in slow tramic is the only additional cost
c. the increased use of gasoline is the only external cost incurred
d. there are mutual external costs from the slow trafic that include increased gasoline costs and more time spent on the roadway
one person isn't the only fixation the world doesn't revolve around yourself so i would say that everyone causes external costs that is in the congested roadway
