题目

三棱锥A—BCD,在面ABC内有一点P,P到平面BCD的距离等于P到AB的距离,则在平面ABC内的P的轨迹为(    ) 答案：解析：如图,作PH⊥AB于H,PE⊥平面BCD于E,PF⊥BC于F,由题意知PE=PH,即其轨道为一条直线,排除A、B两项;又PF＞PH,故D适合.答案：D短文填词（满分10分）Barack Obama, who is the son of a black father from Kenya                          and a white mother from America, was ________in Hunolulu,    小题1:________         Hawaii on August 4th ,1961. He dreamed o______ becoming        小题2:________          the President of the United States _________ he was only a small  小题3:________          boy. In 1988, he was __________(录取) into Harvard Law School,    小题4:________         gained his doctor’s degree in 1991. After ____ from the university 小题5:________          he worked as a lawyer, lecturer and then took u_______ politics.   小题6:________          On November 4, 2008,  Barack Obama’s dream came t______.    小题7:________             The _________(成功) of Obama shows that the black people     小题8:________                who have a dream can reach their g________ and inspired those     小题9:________          who want to cheer the __________（成就）of African Americans.     小题10:________