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:

Personnel department $ $660$

Training department $390$

President$$s salary $440$

Sales manager$$s salary $232$

Other general and administrative $598$

Total SG&A expenses $ $2,320$

Falmouth had $$13,920$ of gross sales to U$.$S$.$ customers and $$3,480$ of gross sales to European customers. Gross income $($sales minus cost of goods sold$)$ from domestic sales was $$3,480$ and gross income from foreign sales was $$1,160.$

Apportion Falmouth's SG&A expenses to foreign source and U$.$S$.$ source income using the following methods:

a$.$ Gross sales. $($Do