A large electric utility company spews million tons of greenhouse gases (mostly carbon dioxide) into the environment each year. This company has committed to spending $ billion in capital over the next five years to reduce its annual emissions by %. More will be spent after five years to reduce greenhouse gases further. a. What is the implicit cost of a ton of greenhouse gas? b. If the United States produces billion tons of greenhouse gases each year, how much capital must be spent to reduce total emissions by % over the next five years based on your answer in Part (a)?

Because of the violent nature of the sport, professional american football players are at risk of suffering concussions (or brain injuries) during the violent collisions that occur between players during the game. violent collisions involving hits to the head are particularly risky. suppose the commissioner of the national football league (nfl) institutes a rule requiring players to wear a new, lighter helmet that is designed to reduce head trauma during collisions between players on the field. while the new helmets the probability of a concussion resulting from each individual collision, at the same time the new helmets could also give football players an incentive to play more , which could potentially the amount of violent collisions and thus the number of concussions suffered by nfl players, all else equal.