Rick Rocker, a citizen and resident of country F, decides to perform a concert in Los Angeles. Country F does not have an income tax treaty with the United States. The U.S. promoter has agreed to pay Rocker $1 million. Rocker himself incurs $200,000 of expenses in connection with the concert. When the promoter pays Rocker his fee, the promoter: should withhold $300,000 of U.S. tax. does not have to withhold any U.S. tax. must withhold tax at Rocker's marginal rates. should withhold $240,000 of U.S. tax.