Describe in words the region of a 3-dimensional space represented by the inequality

Write an equation or inequality that represents a plane containing all points with equal and -coordinates.

Write inequalities to describe the following region:

The solides circular cylinder that lies on or below the plane and on or above the disk in the -plane with centre the origin and radius 2 units.

The sketch of the solid is given below. Given , write the inequalities that describe it.

Describe the surface in 3-dimensional space represented by the equation