Lines, planes and sections in space
Answers are for parents and teachers.
1
How many edges of a cube are skew to a given edge? (From the 12 edges remove the edge itself, the 4 intersecting and the 3 parallel ones.)
4
2
Four points not in one plane (no three on a line): how many planes can be drawn if each time three points are taken?
4
3
Why does a camera tripod stand on three legs?
The leg tips are three points not on one line and exactly one plane passes through them, so the tripod does not wobble even on uneven ground.
4
Name the type of the section ACB₁ of a cube and give the reason.
Equilateral triangle: its sides are face diagonals of the cube.
5
How many edges does a hexagonal pyramid have?
12