A    convex  concave    lens is used to converge light.

A convex lens is used to converge ligtht.

Explanation:

A concave lens is a lens that is thicker on the ends than in the middle. As consequence of this, a concave lens diverges (separate) the rays of light. A concave lens is also called diverging lens.

A convex lens is is thicker in the middle than on the ends. As consequence of this, a convex lense converge the parallel rays that pass through it. A convex lens is also called converging lens.

Ithink its solid. hope this

Bthe s the