[The following information applies to the questions displayed below.] Falmouth Kettle Company, a U.S. corporation, sells its products in the United States and Europe. During the current year, selling, general, and administrative (SG\&A) expenses included: Falmouth had $17,280 of gross sales to U.S. customers and $4,320 of gross sales to European customers. Gross income (sales minus cost of goods sold) from domestic sales was $4,320 and gross income from foreign sales was $1,440. Apportion Falmouth's SG\&A expenses to foreign source and U.S. source income using the following methods: a. Gross sales. (Do not round intermediate calculations.)