I need some help pls!

Using complete sentences, describe the central economic problem facing all humans. why does this require people to make choices? how can this result in opportunity costs?

Gemstones are commonly found in pegmatites, which are igneous rocks that are a. exceptionally mafic b. exceptionally coarse grained c. exceptionally fine grained d. extrusive, forming from lava

Asegment whose endpoints are points on the edge of the circle are whatps: i ment to put this under geometry i apologize ; ;