Márcia e Rodrigo decidiram juntar seus selos e iniciar uma coleção em dupla. Juntos eles têm 1200 selos. Márcia tinha 300 selos a mais que Rodrigo. Com quantos selos Rodrigo contribuiu para iniciar a coleção? ​

Pegmatites are igneous rocks in which the individual minerals are very large. typically, the minerals are all light-colored quartz, feldspar and muscovite. if you were given a black and white photograph of a pegmatite in a quarry (where the rock has been blasted and broken), what physical properties could you use to identify those three minerals in this hypothetical photo? describe each mineral and the specific diagnostic properties. be specific.