What type of CPI bias occurs when consumers switch from buying groceries at their local supermarket to buying them at a discount warehouse like Costco?

Historically, household debt in the U.S. had been:

A. rising steadily since the Great Depression until the early 2000s, when it accelerated. B. rising steadily since the Great Depression until the early 2000s, when it declined. C. fairly constant since the Great Depression until the early 2000s, when it accelerated. D. fairly constant since the Great Depression until the early 2000s, when it declined.

Shama is producing candles in a perfectly competitive market. When she produces 500 candles, her total cost is $250. If she produces one additional candle, her total cost increases to $260

In order to maximize her profit, she should produce the additional candle A) if the market price for a candle is $12. B) only if the market price exceeds $260 for a candle. C) only if the market price exceeds $250 for a candle. D) if the market price for a candle exceeds $0.50. E) if her price exceeds her average total cost.