In the model known as ___, advertisers pay for their ads only when a website visitor clicks on the ad.

Policymakers are provided data about the private and social benefits of a good being sold in the market. quantity private mb ($) social mb ($) 6 6 9 7 4 7 8 2 5 9 0 3 what is the size of the externality? if the externality is positive, enter a positive number. if negative, make it a negative number. $ given this data, policymakers must decide whether to address the associated externality with a subsidy or a tax. as their economic consultant, which of the two policy tools would you recommend? a subsidy a tax

When interest is compounded continuously, the amount of money increases at a rate proportional to the amount s present at time t, that is, ds/dt = rs, where r is the annual rate of interest. (a) find the amount of money accrued at the end of 3 years when $4000 is deposited in a savings account drawing 5 3 4 % annual interest compounded continuously. (round your answer to the nearest cent.) $ (b) in how many years will the initial sum deposited have doubled? (round your answer to the nearest year.) years (c) use a calculator to compare the amount obtained in part (a) with the amount s = 4000 1 + 1 4 (0.0575) 3(4) that is accrued when interest is compounded quarterly. (round your answer to the nearest cent.) s = $

Why do you think the compensation plans differ at the two firms? in particular, why do you think kaufmann’s pays commissions to salespeople, while parkleigh does not? why does parkleigh offer employees discounts on purchases, while kaufmann’s does not?