Answer:
see below
Explanation:
The area of one square face is the square of the edge dimension:
face area = s^2 = (17 mm)^2 = 289 mm^2
A cube has 6 square faces, all with the same area, so the surface area of the cube is ...
surface area = 6 × face area = 6 × (289 mm^2) = 1734 mm^2
___
You don't even need a calculator for this. You can select the appropriate answer by realizing the area of a face is less than (20 mm)^2 = 400 mm^2, and the total area is less than 6×400 mm^2 = 2400 mm^2. Estimating can be your friend.