Assertion (A) : The number of edges in a triangular prism = 9.

Reason (R) : In a triangular prism, the number of vertices = 2 x number of sides = 6;

The number of faces = 2 + number of sides = 5.

1. Both A and R are correct, and R is the correct explanation for A.

2. Both A and R are correct, and R is not the correct explanation for A.

3. A is true, but R is false.

4. A is false, but R is true.

Assertion (A) : The number of edges in a rectangular pyramid = 8.

Reason (R) : In a triangular prism, the number of vertices is one more than number of sides and the number of faces is one less than number of sides.

1. Both A and R are correct, and R is the correct explanation for A.

2. Both A and R are false.

3. A is true, but R is false.

4. A is false, but R is true.

Can a polyhedron have 15 faces, 30 edges and 20 vertices ?

Draw the net of a square pyramid.