11. The imposition of a per unit sales tax on a good will reduce its equilibrium quantity if...
A. the demand is inelastic
B. the demand is elastic
C. the demand is unitarily elastic
D. All of the above are correct
點解ans 係 d
如果就咁看問題 答案係d 係因為
一加價 d人買野就會買少d ( 除左perfeclty)
但係 如果畫返個圖出來
答案唔係應該 a 咩
a 係減左
b 果個我唔識畫 (如果可以教埋就最好)
c unitarily elastic 係 笑果個圖 +同-唔係都冇變個 E 咩