For the first post there will a review on Measurement.

1 gram = 1,000 milligrams

1 kilogram = 1,000 grams

1 tonne = 1,000 kilograms

1 metre = 100 centimetres

1 metre squared = 10,000 centimetres squared

1 metre cubed = 1,000,000 centimetres cubed

1 metre cubed = 1,000 litres

1 centimetre = 1 millilitre

1 litre = 1,000 millilitres

1 litre = 1,000 centimetres

1 centimetre squared = 100 millimetres squared

1 centimetre cubed =  1,000 millimetres cubed