For each case, choose the condition that characterizes demand: elastic demand, inelastic demand, or unit-elastic demand.

a. Total revenue decreases when price increases.

b. The additional revenue generated by an increase in quantity sold is exactly offset by revenue lost from the fall in price received per unit.

c. Total revenue falls when output increases.

d. Producers in an industry find they can increase their total revenues by coordinating a reduction in industry output.