Use the net to compute the surface area of three dimensional figure.

Option C:

Surface area of the three dimensional figure is 166 unit².

Solution:

Let us find the area of the net of the figure.

Length = 7, Width = 5, Height = 4

Area of the bottom = length × width

                                = 7 × 5

                                = 35 unit²

Area of the Top =  length × width

                          = 7 × 5

                          = 35 unit²

Area of the left = width × height

                         = 5 × 4

                         = 20 unit²

Area of the right = width × height

                         = 5 × 4

                         = 20 unit²

Area of the front = length × height

                            = 7 × 4

                            = 28 unit²

Area of the back = length × height

                            = 7 × 4

                            = 28 unit²

Surface area = 35 + 35 + 20 + 20 + 28 + 28

                     = 166 unit²

Surface area of the three dimensional figure is 166 unit².

ab will be equal to