1. Which quantity is the largest: 20 cm, 25 mm, 0.05 m, 2.5 dm?. 2. What physical methods you can use to separate components of a mixture of sand, salt and iron filings (tiny pieces)?

3. A box with cubic shape has each side of 50 mm. What is the volume of the cube in cm3? Volume in liters (L)? .

4. A rectangular piece off silver foil weighs 2.1 g. If the the density of silver is 10.5 g/cm3, what is the volume of the foil? If the length and width of the foil are 10 cm and 5 cm respectively, what is its thickness?