标志中国半殖民地半封建社会完全形成的历史事件是（）。

On May 29, 1973, Thomas Bradley, a black man, was elected mayor of Los Angeles. Los Angeles is the third largest city in the United States, with a population of three million. About sixteen percent of the city’s population are black.
News of this election appeared on the front pages of newspapers everywhere in the United States. Here is how one major newspaper reported the event.
LOS ANGELES ELECTS BRADLEY MAYOR UNSEATING YORTYBLACK WINS 56% OF VOTES
Bradley called his victory over Yorty "the fulfillment of a dream". During his childhood and youth, people had kept telling him, "You can’t do this, you can’t go there, because you are a Negro. " Nevertheless he had won a decisive victory over a man who had been won 43.7 percent.
Los Angeles voters have had many opportunities to judge. Thomas Bradley had to form an opinion of him. The son of a poor farmer Texas, he joined the Los Angeles police force in 1940. During his twenty-one years on the police force he earned a law degree by attending school at night. He was elected to the city council ten years ago.
At the time of the Los Angeles election, three other American cities already had black mayors, but none of those cities had as large a population as Los Angeles. Besides, the percentage of blacks in those other cities was much larger. Cleveland, Ohio, had thirty-six percent black when Carl Stokes was elected mayor of Cleveland in 1967. In the same year Richard Hatcher was elected mayor of Cary. In Newark, New Jersey, sixty percent of the population were black when Kenneth Gibson was elected in 1970. Thus election of a black mayor in those cities was not very surprising.
In Los Angeles thousands of white citizens voted for Thomas Bradley because they believed he would be a better mayor than the white candidate. Bradley had spent forty-eight of his fifty-five years in Los Angeles. Four years ago Bradley lost mayoral election to Yorty. This time Bradley won.

Bradley hit the front page headline for ______.

A. he was the first black mayor in history
B. he was the first black mayor in the south of the USA
C. he was the first black mayor of one of the largest cities in the USA
D. a poor farmer’s son could also win an important election

设A="345678"，则表达式Val(Mid(A,4,2)+Right(A,4))的值为______。

李某为运石头建房租用田某毛驴1头，租期为当年11月20日到次年11月20日。当年12月10日，田某因急需用钱将毛驴卖给了李某，双方于当日签订了合同。次年5月7日该毛驴产下了一头小驴，则小驴应属于谁？（）

A.小驴应归田某所有，因为毛驴的所有权属于田某，其孳息也应归田某

B.小驴应归田某、李某共有，因为小驴是在租用期间生下的

C.小驴应归李某所有，因为双方签订的合同成立时就完成了交付和所有权转移

D.小驴应归田某所有，因为买卖不破租赁，即使所有权发生了转移，孳息也不转移

关于葡萄胎病人出院后定期随访的内容，下列哪项是错误的（）

A.2年内定期随访并应避孕

B.HCG值降到正常后仍需定期复查

C.每次随访均应询问有否异常 * * 出血、咳嗽、咯血

D.每次随访均应做妇科检查有否转移性结节的出现

E.每次随防均应拍摄胸片

某船LBP=68.4m，在Δ=6034t时，纵稳心半径R=79m，则相应的每厘米纵倾力矩MTC=（）×9.81kN.m/cm。

A.77

B.62

C.73

D.70