A wheat producer is willing and able to sell her wheat at a price of $7 per bushel. This works well for her in the first year, but during the second year, the maximum price she is able to get for her wheat is $5 per bushel. Explain whether or not each of the scenarios a.-e. could be the reason behind this change. 

a. An increase in wheat production technology

b. A price floor above the first year equilibrium price

c. An increase in wheat consumers' incomes

d. A decrease in population

e. A price ceiling below the first year equilibrium price