hey user!
your answer is here...
given that Chris wants to make a wooden puzzle shaped like a cube and the length of each edge of the cube is 1/3 foot.
we know that 1 foot = 30cm
therefore 1/3 foot = 1/3 × 30
= 10 cm
the side ( edge ) of the cube is 10cm
hence, total surface area of the cube = 6s²
= 6 × 10²
= 6 × 100
= 600cm²
cheers!!