题干

如图,一栋建筑物AB的高为(30﹣10 3 )m,在该建筑物的正东方向有一个通信塔CD,在它们之间的地面点M(B,M,D三点共线)处测得楼顶A,塔顶C的仰角分别是15°和60°,在楼顶A处测得塔顶C的仰角为30°,则通信塔CD的高为(   )

A:30m

B:60m

C:30 3  m

D:40 3  m

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答案(点此获取答案解析)

B

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    I was sitting the surgical waiting area at the hospital waiting for word of my wife's operation The small room was filled with other families and friends,who were1waiting to hear how their loved ones were doing.

    There was a young boy siting quietly in the2He held a small box of 3in one hand and a tablet(写字板)in the other Every so often he'd place the tablet on his lap and draw something.As the hours passed I began to see the room almost4And there was a strange silence.

    "Daddy, when is Mommy going home?"the young boy asked,breaking the 5

    "Tomorrow." his father replied The boy picked up his crayons(蜡笔)and6something on the tablet.

    I7 him as he moved his feet back and forth,looking up at the ceiling and then toward the sunshine-filled window.When's8Daddy?"he asked. His father 9 him over to sit by him."Come,10here next to me."he said with a gentle tone in his voice11his things,the little boy walked slowly to his father's side from the corner.The man12out and held his son by his shoulder.

    There are three days in life Yesterday today and tomorrow.One is over and done,one we live in,the other we 13We cant live in yesterday, but if we are happy enough today. we will be even happier tomorrow."he said in an attempt to14the boy.

    The little boy looked at him for a moment and said."If Mommy is going home tomorrow.I'll be15So.I want it to be tomorrow already. Daddy"

    Now hanging on every word of this16I leaned forward to hear his response.It was17.

    “Son, the one great thing about today is once it18it is already almost tomorrow.”

    I thought about how19 it was. Even in my adult life,I still live waiting for what tomorrow may 20.

    Now I know that it is already“almost tomorrow”.