1. Inelastic demand always takes a value between zero and -1.
2. Elastic demand has an absolute value greater than 1.
3. Demand is inelastic when the percentage change in quantity demanded is smaller than the percentage change in price.
4. Demand is elastic when the percentage change (decrease) in quantity demanded is larger than the percentage change (increase) in price.

Which of these statements about the shape of demand curves and elasticity are true?