Which of these geometric figures can intersect to form a cross section? Check all that apply. 1.a line and a prism 2.a line and a rectangle 3.a point and a prism 4.a prism and a horizontal plane 5.a vertical plane and a pyramid        Check all that apply

A cross section is formed by the intersection of a three-dimensional object and a plane.

So the right answers are 4 and 5.

Let's explain each case.

First. A prism and a horizontal plane

The representation of this statement is shown in Figure 1. A prism has the following characteristics:

1. These objects have identical ends.
2. They have flat faces.
3. They have the same cross section all along its length 

So in the figure, you can see how the horizontal plane intersects the prism. The cross section of this object is a triangle. Thus, it has the same cross section all along its length and this object is called a triangular prism.

Second. A vertical plane and a pyramid

As shown in Figure 2 you can see the representation of this statement. If the pyramid is cut with a plane that passes through the top vertex and it is perpendicular to the base, then the intersection of this pyramid and the plane becomes a triangular cross section.