In: Economics
a) In the 1st year demand is relatively inelastic. Hence when a tax is imposed on buyers, demand decreases and this shifts the demand down. Deadweight loss (shown by black shaded region) is small. In the fifth year the demand becomes elastic. Hence, the same tax now generates a lower deadweight loss.
b) In the 1st year demand is relatively inelastic. Hence when a tax is imposed on buyers, demand decreases and this shifts the demand down. Revenue (shown by green shaded region) is large in first year. In the fifth year the demand becomes elastic. Hence, the same tax now generates a lower tax revenue.