I know this is last minute but I can see some people are here, so I was just wondering about question 2b from the sample exam. 2b asks 'Explain why an economy must achieve productive efficiency in order to achieve allocative efficiency. (3 marks)'. From my understanding, allocative efficiency refers to allocating resources in a way that maximises society's wellbeing, and productive efficiency is essentially maximising production and productivity, and lowest cost, but I don't understand why productive efficiency has to be achieved first. Is it because productive efficiency essentially lowers the prices that are offered to consumers and that this maximises societal wellbeing? This confuses me a bit.