4. Using diagrams show what changes in price and quantity would be expected under the following scenarios. Also, state whether each scenario results in a change in demand or a change in quantity demanded.

a. Chicken Production - A new variety of chicken feed cuts the production costs for chicken farmers.

b. Red Raspberries - A new nationwide consumer health report shows that eating red raspberries decreases the risk for developing certain cancers.

c. Air Travel - Worries about air safety cause travelers to shy away from air travel.

d. Gasoline - A Tornado destroys several major oil refineries in Texas and it becomes more difficult to refine and transport crude oil.