Armac Ltd. is a sluice-box manufacturer based in China. A sl…

Armac Ltd. is a sluice-box manufacturer based in China. A sluice-box is used for gold prospecting. Armac is interested in selling a few of its machines to an American mining company, but it wants 95 percent of the machines’ price in gold and the rest in ores recovered by using the machines. This is an example of a ________.