题干

在四棱锥P﹣ABCD中,AB∥CD,AB=
1
2
DC=1,BP=BC=2,PC=2,AB⊥平面PBC,F为PC中点.
(Ⅰ)求证:BF∥平面PAD;
(Ⅱ)求证:平面ADP⊥平面PDC;
(Ⅲ)求VP﹣ABCD.
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答案(点此获取答案解析)

(Ⅰ)证明:取PD的中点为E,连接EF,
∵F为PC中点∴EF为△PDC的中位线,
即EF∥DC且EF=
1
2
DC.
又∵AB∥CD,AB=12

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阅读下面短文,从短文后各题所给的四个选项(A、B、C、D)中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。

    Walt Disney was born on December 5, 1901 in Chicago Illinois while he lived most of his childhood in Marceline, Missouri.

    Since young, Walt showed great 1 in art. He would often sell drawings to neighbors to make 2 money. Though his father could be quite 3, and often there was little money in the family, Walt was 4 by his mother, and older brother to 5 his attention on what he loved deeply.

    In 1918, Disney 6 to enter the army. However, he was 7 because he was under age, only 16 at the time. 8, Walt joined the Red Cross and was 9 to France, where he spent a year driving an ambulance(救护车).His ambulance was 10 not with army camouflage(伪装),but with Disney cartoons.

    Once Walt 11 from France to America, he started a small company which finally 12 to be a failure. With twenty dollars, Walt  13 for Hollywood to try his luck. After making a  14 of his “Alice Comedies”, Walt became a(an) 15 Hollywood figure. In 1932, Flowers and Trees(the first color cartoon) 16 Walt the first of his studio's Academy Awards. His dream of a clean, and organized amusement park  17 as Disneyland Park opened in 1955.

    Walt Disney is a hero of the 20th century. His worldwide popularity was 18 on the ideals(标准): imagination, creation and self-made success in the American 19. He brought us closer to the future 20 telling us of the past. It is certain that Walt Disney is a great man.