Smith, a divorced person, provided over one-half the support for his widowed mother, ruth, and his son, clay, both of whom are u. s. citizens. during this year, ruth did not live with smith. she received $9,000 in social security benefits—none of which was taxable. clay, a full-time graduate student, and his wife lived with smith. clay had no income but filed a joint return, owing an additional $500 in taxes on his wife's income. how many exemptions was smith entitled to claim on his tax return?

Druganaut company buys a $21,000 van on credit. the transaction will affect the

4. suppose that pollution in a neighborhood comes from two factories, with marginal benefit curves given by mb1 = 12 – p1 and mb2 = 8 – p2. the level of pollution in the neighborhood is given by p = p1 + p2. the government wants to limit pollution by instituting a pollution-rights market. the government’s desired level of p is 10, so it prints 10 pollution rights and offers them for sale to the firms. a)find the equilibrium selling price of a pollution right, as well as the allocation of rights (and hence pollution levels) across the two factories. b)repeat part (a) for the case where the government’s desired level of pollution equals 14. c)comment on the usefulness of a pollution rights market in achieving efficient levels of pollution abatement.

When cell phones were first entering the market, they were relatively large and reception was undependable. all cell phones were essentially the same. but as the technology developed, many competitors entered, introducing features unique to their phones. today, cell phones are only a small fraction of the size and weight of their predecessors. consumers can buy cell phones with color screens, cameras, internet access, daily planners, or voice activation (and any combination of these features). the history of the cell phone demonstrates what marketing trend?