the firgure below shows the demand and suplly for milk tea

Question 2. (15 pts) The figure below shows the demand and supply for milk tea. 120 P S 100 80 60 40 20 D 0 0 1 2 3 4 5 0 6 a. Calculate the price elasticity of demand (PED) when the price of milk tea rises from VND 20 thousand to VND 40 thousand. Is the demand elastic, inelastic, or unit elastic? (4+2 pts) b. Calculate the price elasticity of supply (PES) when the price of milk tea declines from VND 100 thousand to VND thousand 80. Is the supply elastic, inelastic, or unit elastic? (4+2 pts) c. Over what price range is the demand for milk tea elastic? (3 pts)