答：按平米出售，10mm厚的每平米15公斤。15mm厚的每平米重量22.5公斤，以此类推。

3, Press what unit to sell?How many kilograms per square meter?

Sell by square metre, 10mm thick every square metre 15 kilograms. It is 15mm thick and weighs 22.5 kilograms per square meter. And so on.