1. Why not impose tariffs on all products? What economic arguments would you use to defend or criticize the use of tariffs?

2. Most of the world has floating exchange rates, but the Euro Zone combined the currencies of 17 countries to in effect, a fixed exchange rate between them.China has a fixed exchange rate with the US dollar, and undervalues its exchange rate by 17% - 19%, thus giving them an unfair advantage in international exchange.Should the world governments get together and set up a common rule for currency exchange?Discuss about that, please.

Thank you