Explanation:

To find the volume of the metal, you need to calculate the difference between the volume of the outer box and the inner box.

- Outer dimensions of the box are 15 cm x 18 cm x 8 cm.

- Volume = 15 x 18 x 8 = 2160 cm³.

- Inner dimensions: Reduce each dimension by twice the thickness (1.5 cm x 2 = 3 cm).

- New dimensions = 12 cm x 15 cm x 5 cm.

- Volume = 12 x 15 x 5 = 900 cm³.

- Volume of the metal = Outer Volume - Inner Volume

- 2160 cm³ - 900 cm³ = 1260 cm³.

- Options:

- Option 1: 1680 cm³

- Option 2: 950 cm³

- Option 3: 1440 cm³

- Option 4: 1260 cm³