Answer:
Option D is correct
Surface area of a cube is 294 square units
Step-by-step explanation:
Surface area of a cube is given by:
square unit
where
S is the surface area of a cube
a is the length of edge of a cube.
From the given figure, we have;
a = 7 units
then;
square units
Therefore, the Surface area of a cube is 294 square units