Question: The ruler during the Tiananmen square protests of the country first to buy the Curtiss P-36 Hawk fathered what son?

<P0-S0> Internal company designation for a simplified export version with fixed landing gear, two slightly differing aircraft built, first sold to China, second to Argentina <SEP> <P1-S0> born in chongqing in 1955, xu grew up in beijing. <P1-S1> his father was the head of the history department at peking university. <P1-S2> in 1975, near the end of the cultural revolution, he was relocated to the countryside for two years as part of mao zedong's "re-education" policy. <P1-S3> returning to beijing in 1977, he enrolled at the central academy of fine arts(cafa) where he joined the printmaking department and also worked during a short period of time as a teacher, receiving his masters in fine art in 1987. after the tiananmen square protests of 1989 his recent work came under scrutiny from the government and received harsh criticism for what was perceived as a critique of the chinese government. <P1-S4> due to the political pressure and artistic restrictions of the post-tiananmen period in china, xu bing, like many of his contemporaries, moved to the united states in 1990 where he was invited by the university of wisconsin–madison. <P1-S5> he then resided to the united states until his appointment as vice-president of the beijing cafa in 2008. <SEP> <P2-S0> He is mostly known for being crippled by the Red Guards and becoming a paraplegic. <P2-S1> He has since dedicated his life to improving the rights of people with disabilities. <P2-S2> Deng Pufang () (born 16 April 1944) is the first son of China's former Paramount leader Deng Xiaoping. <SEP> <P3-S0> Party and government leaders Name Position (s) in 1989 Deng Xiaoping Chairman of the Central Military Commission; de facto ``paramount leader ''Chen Yun Chairman of the CPC Central Advisory Commission Zhao Ziyang General Secretary of the Communist Party of China First Vice-Chairman of the Central Military Commission Li Peng Premier of the People's Republic of China Qiao Shi Secretary of the CPC Central Commission for Discipline Inspection Secretary of the CPC Political and Legislative Affairs Committee Hu Qili First Secretary of the Secretariat of the Communist Party Yao Yilin First Vice Premier of the People's Republic of China Yang Shangkun President of the People's Republic of China Vice-Chairman of the Central Military Commission Li Xiannian Chairman of the Conference National Committee Wan Li Chairman of the Congress Standing Committee Wang Zhen Vice President of the People's Republic of China Jiang Zemin Communist Party Shanghai Municipal Secretary Li Ximing Communist Party Beijing Municipal Secretary Zhu Rongji Mayor of Shanghai Chen Xitong Mayor of Beijing Hu Jintao Communist Party Tibet Regional Secretary Wen Jiabao Chief of the General Office of the Communist Party of China Bold text indicates membership in the Politburo Standing Committee Italics text indicates Great Eminent Officials <SEP> <P4-S0> the events of the full - blown revolution began in poland in 1989 and continued in hungary, east germany, bulgaria, czechoslovakia and romania. <P4-S1> one feature common to most of these developments was the extensive use of campaigns of civil resistance, demonstrating popular opposition to the continuation of one - party rule and contributing to the pressure for change. <P4-S2> romania was the only eastern bloc country whose people overthrew its communist regime violently. <P4-S3> protests in tiananmen square (april to june 1989) failed to stimulate major political changes in china, but influential images of courageous defiance during that protest helped to precipitate events in other parts of the globe. <P4-S4> on 4 june 1989 the trade union solidarity won an overwhelming victory in a partially free election in poland, leading to the peaceful fall of communism in that country in the summer of 1989. hungary began (june 1989) dismantling its section of the physical iron curtain, leading to a exodus of east germans through hungary, which destabilised east germany. <P4-S5> this led to mass demonstrations in cities such as leipzig and subsequently to the fall of the berlin wall in november 1989, which served as the symbolic gateway to german reunification in 1990.