I am not happy with the calculation of the the changed producer surplus as I think it should be a smaller triangle, thanks !

consumer surplus 3.4 producer surplus D 02 300 2500 Q P consumer surplus 5 tax deadweight loss 3.8 2.6 producer surplus 1.4 D 0.2 2500 600 Demand is given by P = 5 - 0.002Q, and supply is given by P = 0.2 + 0.004Q. In equilibrium, we get 5 - 0.002Q = 0.2 + 0.004Q, which solves for Q = 800 and P = 3.4. With tax, the new supply curve is: P = 1.4 + 0.004Q. When we solve 5 - 0.002Q = 1.4 + 0.004Q, we get 3.6 = 0.0060 so Q = 600 and P = E3.8. This is the price paid by the buyer, let's label it Pb = E3.80. The supplier gets the price paid by the consumer minus tax Ps = 3.8 - 1.2 = 62.6. The effects of the tax on suppliers is 3.4 - 2.6 = 0.8(they now get less revenue from each litre sold), and on consumers it is 3.8 - 3.4 = 0.4 (they now pay more per litre). The consumer surplus before the tax is [(5 - 3.4) . 800]/2 = $640. The producer surplus before tax is [(3.4 - 0.2) . 800]/2 = E1280. The consumer surplus after the tax is [(5 - 3.8) . 600]/2 = E360. The producer surplus after the tax is [(2.6 - 0.2) . 600]/2 = $720. Lost consumer surplus is E280. Lost producer surplus is $560 The deadweight loss = 1/2 . (800 - 600) . (3.8 - 2.6) = E120.The demand for petrol is P = 5 0.002Q and the supply is P = 0.2 + 0.00412, where P is in pounds and Q is in litres. If a tax of 1.20 per litre is placed on petrol, what are the effects? What is the lost consumer surplus? What is the lost producer surplus? What is the deadweight loss