Price of gasoline is well above $4 per gallon all over the United States, and over $5 per gallon in some parts of the country. Is this due to a shift of the supply curve, or a shift of the demand curve or a shift of both the supply and demand curves. If you believe that the supply curve has shifted, please explain in what direction the supply curve has shifted and why it has shifted. If you believe that the demand curve has shifted, please explain in what direction the demand curve has shifted and why it has shifted.