Answer

8.Suppose you observe that the equilibrium price and quantity of "sports sandals" has risen in the last year. A possible explanation for this would be:

An increase in the "hipness quotient" of "sports sandals".
A reduction in the cost of materials used in making the sandals.
A decrease in the price of other kinds of shoes.
An increase in the wages of shoe factory workers.
A decrease in the wages of shoe factory workers.