Explanation:

- First, calculate the volume of the cuboid: V = 5 cm × 10 cm × 20 cm = 1000 cm³.

- Since the cube has the same volume, find the side length of the cube: s = ³v1000 cm = 10 cm.

- Now, calculate the total surface area of the cuboid: SA_cuboid = 2(5×10 + 10×20 + 20×5) = 700 cm².

- Calculate the total surface area of the cube: SA_cube = 6×(10×10) = 600 cm².

- The ratio of the surface areas is 700:600, which simplifies to 7:6.

Correct Answer: Option 2, 7 : 6