1. The owner of a tropical forest harvests timber so as to maximize his own profit from the land. This forested land also provides habitat for wild beehives that pollinate the crops of surrounding farmers. Assume that the number of bees and therefore the magnitude of the pollination services provided are proportional to the size of the intact forest habitat on the landowner's property. In the absence of an agreement between the landowner and his neighbors, is he likely to harvest too much or too little of his timber at any given time?

Characterize this as an example of a positive or a negative externality.

2. The efficient level of a negative externality is always a positive amount (circle one: True/False). Briefly explain your answer.

3. Examine the graph of marginal benefits and costs of abatement below. Suppose regulators expect these curves to be as shown but are uncertain as to whether or not the marginal costs of abatement curve will be higher or lower than depicted. If regulators must choose between an emissions tax or tradable quotas, which would be preferred from the perspective of efficiency, given the uncertainty in costs of abatement? Explain in a short paragraph and illustrate on this graph.