Context: Paper is often characterized by weight. In the United States, the weight assigned to a paper is the weight of a ream, 500 sheets, of varying "basic sizes", before the paper is cut into the size it is sold to end customers. For example, a ream of 20 lb, 8.5 in × 11 in (216 mm × 279 mm) paper weighs 5 pounds, because it has been cut from a larger sheet into four pieces. In the United States, printing paper is generally 20 lb, 24 lb, or 32 lb at most. Cover stock is generally 68 lb, and 110 lb or more is considered card stock.

Question: What characteristic is paper usually classified by?
Answer: weight

Question: In the US, the weight of what is used to classify paper for sale?
Answer: a ream

Question: Paper rated at over 110lb is considered what type of stock?
Answer: card

Question: What is weight most often characterized by?
Answer: Unanswerable

Question: How many sheets of reams are in a basic size?
Answer: Unanswerable

Question: In what sizes do pounds of paper come?
Answer: Unanswerable

Question: What happens to the paper after it is sold to end customers?
Answer: Unanswerable

Question: How much does a ream of 5 lb, 8.5 in x 11 in paper weigh?
Answer: Unanswerable

Question:  What characteristic is paper not usually classified by?
Answer: Unanswerable

Question:  In the UK, the weight of what is used to classify paper for sale?
Answer: Unanswerable

Question:  Paper rated at over 210lb is considered what type of stock?
Answer: Unanswerable