Which of the following statements is true?

a. The price elasticity of supply measures the relative change in the quantity supplied that results from a change in price.

b. If the supply price elasticity is greater than 1, it is elastic; if it is less than 1, it is inelastic.

c. Supply tends to be more elastic in the long run than in the short run.

d. The relative elasticity of supply and demand determines the distribution of the tax burden for a good.

e. All of these statements are true.