1 Circle the letter with the correct solution or answer. The total distance around the 2D shape is A volume, B perimeter, C area, D kilometer. 1.2 The name of the 3D object below is A rectangle prism, B triangular pyramid, C rectangular pyramid, D triangular prism.

• Volume is the amount of space a 3D object occupies.
• Perimeter is the total distance around the boundary of a 2D shape.
• Area is the amount of surface a 2D shape covers.
• Kilometer is a unit of length.

The "total distance around the 2D shape" is the definition of perimeter.
The answer is $\boxed{\text{B. Perimeter}}$.

The object has a base that is a rectangle and four triangular faces that meet at a single point (apex).

A 3D object with a polygonal base and triangular faces meeting at an apex is called a pyramid. Since the base is a rectangle, it is a rectangular pyramid.
The answer is $\boxed{\text{C. Rectangular pyramid}}$.