What type of force are you exerting when you lie on a bed

Explain why the aperture of the spherical mirror should be small compared to the radius of curvature of the mirror.

Asample of a gaseous substance changes into liquid. this process is called (blank) and it takes place when heat is (blank) a gaseous system

Abearing is designed to a reduce friction b. support a load c.guide moving parts such as wheels, shafts and pivots d. all of the above