1/ Suppose the market shares of all airlines in a city-pair air market is as follow: 13%, 25%, 14%, 4%, 10%, 9%, 8%, 7%, 10%. Please calculate CR4 and HHI index respectively. Please state what kind of market it would be for this city-pair market?

2/Please explain the idea of price discrimination and its application in airline pricing strategy.

3/ Ever since the 1980s, the hub-and-spoke system has been widely used in airline network designing. Please tell us your understanding of the system, including its advantages and disadvantages.

4/ Nowadays low-cost carriers (LCCs) occupy more and more market shares in the air transport market. More and more new LCCs appeared in the market, as network carriers also established their LCC subsidiaries. There also exist negative remarks about LCCs mode, suggesting excessive price competition and cost reduction may also lower safety standards of LCCs.

GIVE ME MORE LONG EXPLANATION AND EXAMPLES.