qnli question: How much money in trade does Australia's largest and busiest seaport handle? sentence: Melbourne houses the headquarters for many of Australia's largest corporations, including five of the ten largest in the country (based on revenue), and four of the largest six in the country (based on market capitalisation) (ANZ, BHP Billiton (the world's largest mining company), the National Australia Bank and Telstra), as well as such representative bodies and think tanks as the Business Council of Australia and the Australian Council of Trade Unions.