Question

which diagram is a net for the cube? what is the surface area of the cube? square millimeters

Explanation:

Step1: Recall cube - net property

A cube net is a 2 - D shape that can be folded to form a 3 - D cube. A standard cube net has 6 square faces.

Step2: Analyze the given diagrams

Both of the given diagrams are valid cube nets as they are composed of 6 congruent squares which can be folded to form a cube.

Step3: Recall surface - area formula for a cube

The surface - area formula of a cube with side length \(s\) is \(SA = 6s^{2}\).

Step4: Identify the side length

The side length of the cube \(s=20\) mm.

Step5: Calculate the surface area

Substitute \(s = 20\) into the formula: \(SA=6\times(20)^{2}=6\times400 = 2400\) square millimeters.

Answer:

Both diagrams are nets for the cube. The surface area of the cube is 2400 square millimeters.