18.【解析】(1)易知BB1⊥CB,∵BC=√3,AB=1,AC=2,∴BC2+AB2=AC2,BC⊥AB,-2分又BA∩BB1=B,BA,BB1c平面ABB1A1,∴BC⊥平面ABB14,一3分∵BEc平面ABB14,BC⊥BE,分∵E为AA的中点,∴AE=AE=1,BE2=BE2=2,∴BE2+B1E2=B1B2,BE⊥BE5分又BE∩BC=B,BE,BCc平面BCE…BE⊥平面BCE·分又BEC平面BCE,平面EBC⊥平面EBC1(2)由(1)知BC⊥AB,∵AB⊥B,BB∩BC=B,BB,BCc平面BCCB,∴AB⊥平面BCCB,8分又AA∥B1B,BBc平面BCCB,AAg平面BCCB,∴AA∥平面BCCB,…点E到平面BCCB的距离为线段AB的长10分SA√×2×1=当12分

书面表达One possible version:NOTICEA sports meeting will be held in the playground of our school from next Thursday to FridayAs you know, the pressure of study is very heavy now, especially for those senior 3. So the purpose of the sports meeting is to letevery student get relaxed, as a result of which we students can live happily and heal thilyEveryone is welcome to take part in it. Those who perform excellently at the sports meeting will get prizes. But don' t take theresults so serously because taking part is more important than the result. Good luck to everyone!

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