Show the effects of the following commodity taxes on a graph. For each tax clearly illustrate and label the tax burden of consumers and producers.
a. An ad valorem tax levied on producers of a good for which the supply curve is upward sloping and the demand curve is downward sloping.
b. A unit tax levied on producers of a good for which demand is infinitely elastic.
c. An ad valorem tax levied on consumers of a good for which demand is very elastic and supply is perfectly inelastic.