The quartz is more resistant to abrasion and chemically more resistant than the feldspar. The result is that the quartz remains in the stream but the feldspar breaks down to clay or is dissolved.
(this is from coursehero.com)
Relative dating<span> is the science of determining the</span>relative<span> order of past events (i.e., the age of an object in comparison to another), without necessarily determining their absolute age, (i.e. estimated age).</span>
1. evaporation because in the water cycle the water turns to water vapor during evaporation
Http://www.lcps.org/cms/lib4/va01000195/centricity/domain/4153/study%20guide%20-%20geography%20unit%201%20answer%20key.pdf