Include correctly labeled diagrams, if useful or required, in explaining your answers. A correctly labeled diagram must have all axes and curves clearly labeled and must show directional changes. If the question prompts you to "Calculate," you must show how you arrived at your final answer.

Assume gadgets are sold in a competitive market, the equilibrium price is $6, and the equilibrium quantity is 500 units.

(a) Using the numerical values above, draw a correctly labeled graph of the market for gadgets and show each of the following.

(i) The equilibrium price

(ii) The equilibrium quantity

(b) At a price of $8 per unit, will there be a surplus or a shortage in the market? Explain.

(c) Assume gadgets now become more popular. On your graph in part (a), show the effect of the increase in gadgets' popularity on the equilibrium price and quantity of gadgets.

(d) Assume instead there is an increase in the price of tin, a major input in producing gadgets. What will be the effect of an increase in the price of tin on the market for gadgets?

(e) If both changes in part (c) and part (d) occurred simultaneously, will the equilibrium quantity of gadgets increase, decrease, remain unchanged, or be indeterminate? Explain.