earth science assignment help

I have this question that I cannot understand. Any help would be appreciated
You are a geologist sampling a mountain peak made of grey volcanic rock. Your analysis of the mineral content in the rock samples indicates the rock contains a low amount of sodium-rich plagioclase, some orthoclase, and high levels of muscovite. What does this tell you about the following?

a) The chemical composition of the magma

b) The branch of Bowen’s reaction series it formed in

c) The relative age of the mountaintop

d) The origin of the rock (extrusive or intrusive)