Answer:
Around 100,i.e. 105
Step-by-step explanation:
In the given cube
Length of the cube = 7 unit cells
Breadth of the cube = 3 unit cells
Height of the cube = 5 unit cells
Therefore the number of unit cubes required to make such big cube is nothing but the volume of the big cube = length*breadth*height
⇒Number of cubes used to make that big cube= 7*5*3
= 105
Hence, option D (around 100) is the correct answer
Answer:
1222
Step-by-step explanation:
You have a triangular prism on top of a rectangular prism. The surface area is the sum of the areas of the exposed faces.
Starting with the triangular prism, the surface area is the area of the two triangular bases plus the area of the two rectangular sides (the bottom rectangular face is ignored).
A = ½ (10) (12) + ½ (10) (12) + (13) (9) + (13) (9)
A = 60 + 60 + 117 + 117
A = 354
The surface area of the rectangular prism is the area of the two rectangular bases (front and back), plus the two walls (left and right), plus the bottom, plus the top (minus the intersection with the top prism).
A = (19) (11) + (19) (11) + (9) (11) + (9) (11) + (19) (9) + (19) (9) − (10) (9)
A = 209 + 209 + 99 + 99 + 171 + 171 − 90
A = 868
So the total surface area is:
354 + 868
1222