Answer:
The surface area of the rectangular prism is 700 units² ⇒ answer A
Explanation:
* Lets revise how to find the surface are of the rectangular prism
- The rectangular prism has 6 rectangular faces
- Each two opposite faces are equal
- It has 4 side faces and 2 bases
* We can find the surface area of it by adding the area of
the 6 faces
- In the problem
# The dimensions of the bases are 12 units and 14 units
# The dimensions of the side faces are 12 units and 7 units,
14 units and 7 units
* Now lets find the area of each 2 equal faces
- In the bases
∵ Area of the rectangle = length × width
∴ The area of one base = 12 × 14 = 168 units²
∴ The area of the two bases = 2 × 168 = 336 units² ⇒ (1)
- In the two opposite faces with dimensions 12 units and 7 units
∵ The area of one face = 12 × 7 = 84 units²
∴ The area of the two faces = 2 × 84 = 168 unit² ⇒ (2)
- In the two opposite faces with dimensions 14 units and 7 units
∵ The area of one face = 14 × 7 = 98 units²
∴ The area of the two faces = 2 × 98 = 196 unit² ⇒ (3)
* To find the surface area of the prism add (1) , (2) , (3)
∴ The surface area of the prism = 336 + 168 + 196 = 700 units²
* The surface area of the rectangular prism is 700 units²