The US Government's Focus on Supply Reduction Efforts in Its "War

The U.S. government's focus on supply reduction efforts in its "war on drugs" has been relatively unsuccessful at addressing illegal drug use. Some economists believe that a successful anti-drug program must concentrate on reducing demand; for example, through drug education and voluntary treatment programs for addicts.
a. Suppose the price elasticity of demand for cocaine is -0.5. What will happen to the equilibrium price, quantity and total revenue from cocaine sales if the government succeeds in its efforts to reduce demand? What is likely to happen to the incentive to sell cocaine?
b. Suppose the government continues to concentrate its efforts on supply reduction and is able to reduce the supply of cocaine. As a result of the reduction in supply the price of cocaine increases by 25 percent. If the price elasticity of demand is -0.5, what is likely to happen to the incentive to sell cocaine?
c. Based on your answers, explain why one approach might be preferred over the other.