Insert an appropriate article in each blank, using ∮ to stand for ZERO article:When your personal wealth is greater than [1] ________ gross domestic product of a small European country, finding [2] ________ incentive (动机）to get out of [3] ________bed on [4] ________chilly Monday morning in Seattle is never going to be easy. So it's perhaps no great surprise that Bill Gates, [5] ________world's richest man, has decided to walk away from lhis day-to-day involvement with Microsoft, and use his full attention to oversee how [6] ________Bill and Melinda Gates Foundation spends its ￡16 billion on philanthropy (慈善）.Ever since [7] ________industrial revolution, wealthy self-made businessmen and women have felt [8] ________calling to create [9] ________legacy (遗赠；遗产）that goes beyond [10] ________profit and loss sheet. The saying "He, who dies rich, dies disgraced" runs deeply through [11] ________business community.Out of all [12] ________great philanthropists, the career path of Bill Gates appears to be [13] ________closest to that of [14] ________oil millionaire John Rockefeller, [15] ________founder of Standard Oil -- [16] ________company that eventually evolved into [17] ________ExxonMobil. Both were self-made men and both became [18] ________richest men on [19] ________planet. Rockefeller was in his late fifties when he turned his attention full time to philanthropy. Now Gates follows suit in his early fifties. "It was [20] ________hard decision for me," he said recently. "I'm very lucky to have two passions that I feel are so important and so challenging.""With great wealth comes great responsibility." He adds.