Answer:
d. All of the above are correct.
Explanation:
a. This tax causes the demand curve for fountain drinks to shift downward by $0.50 at each quantity.
b. The price paid by buyers is $0.30 per drink more than it was before the tax.
This is true as the difference between $0.50 and $0.20 is $0.30. The price paid by buyers is indeed $0.30 per drink more than it was before the tax.
c. Forty percent of the burden of the tax falls on the sellers.
This is true as $0.20 of $0.50 is 40% and this tax burden falls on the sellers.