<prompt> Translate the following text to EnglishIdadi ya knot kwa sentimeta mraba ni kuanzia 20 hadi 30 kwa ajili ya carpet ya sufu ya kijivu hadi 100 hadi 200 kwa ajili ya carpet ya hariri ya bei ghali zaidi, ambayo inaweza gharama maelfu ya pauni.  <response>: The number of knots per square centimetre ranges from 20 30 for a coarse wool carpet to 100 200 for the most expensive silk carpets, which can cost tens of thousands of pounds. 