Question

choose all the figures that have a rectangular cross - section.

Explanation:

1. Triangular pyramid (first figure): A cross-section parallel to its base is a triangle, and any other cross-section cannot form a rectangle, as its faces are all triangles.
2. Cube (second figure): A cross-section parallel to its faces is a square (a special type of rectangle), and cross-sections at certain angles can also form non-square rectangles.
3. Square pyramid (third figure): A cross-section parallel to its base is a square, but slicing parallel to a pair of opposite edges creates a rectangular cross-section.
4. Cylinder (fourth figure): A cross-section perpendicular to its circular bases is a rectangle.
5. Cone (fifth figure): All cross-sections are circles, ellipses, parabolas, hyperbolas, or triangles, never a rectangle.

Answer:

• □ (second figure: Cube)
• □ (third figure: Square pyramid)
• □ (fourth figure: Cylinder)