Why does specialization cause people to trade?

Describe a situation in which a surplus occurs? Is Portugal developed or undeveloped economy? Why do fast food companies compete with each other? What is primary production? Is it possible to achieve economic growth without compromising the environment? How many US dollars is 10 shillings? How much would it cost to start a dairy farm? What is a simple way to describing cost benefit analysis? What does economically active mean? What was the 1974 oil crisis? How much money is 200 kilos in dollars? What does economic down-term mean? What was the economic problem facing returning war veterans in World War 1? What is an example of econmic? Is all government spending counted in GDP? Gas prices in 1991? What are Advantages Of Forestry? How much money does Swift move daily? How did cornflakes change the world? How much I can get for one dollar coin 1920?