What are the measures of ∠1, ∠2, and ∠3?

The radius of the earth is two times the radius of the moon. what fraction of the volume of the earth is the volume of the moon?

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.