The U.S Government is thinking of combating obesity by imposing a ‘fat tax’ on unhealthy foods.  Under the tax, a $4 cheeseburger would cost an extra 80 cents. Researchers say a fat tax could drop obesity rates by 3.5% and prevent 2,700 heart-related deaths a year. Do you agree? Is a ‘fat tax’ a good or bad idea? Is it fair?