题干

如图,一楼房AB后有一假山,其坡度为i=1: 3 ,山坡坡面上E点处有一休息亭,测得假山坡脚C与楼房水平距离BC=25米,与亭子距离CE=20米,小丽从楼房顶测得E点的俯角为45°,求楼房AB的高.(注:坡度i是指坡面的铅直高度与水平宽度的比)
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解:过点E作EF⊥BC的延长线于F,EH⊥AB于点H,
在Rt△CEF中,

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    Do you want to improve your networking skills? If so,check out five ways to promote your networking skills.

    Research the event before you go.

    Do your research before you attend an event.Figuring out the dress standard and the theme of the event will help you perfect your clothes, attitude, and approach____Mental preparation will help you feel confident and comfortable.

    Describe yourself differently.

    Most people choose to describe themselves to strangers by saying their name and job. However, unless you have a unique name and an eye-catching job, this probably won't help. Give them a little more to work with____In that case, people may have a chance to ask you a few questions.

    Network with everyone.

    At networking events, there are probably specific people that you want to talk to.While this could be beneficial to you, don't cut off your other choices____It can also help you to get noticed by the people you want to speak to.

    Smile to make a great first impression.

    ____ According to a research,people decide whether you are trustworthy or not after looking at your face for 34 milliseconds(毫秒).Make those milliseconds count by relaxing the muscles in your face and smiling.

____

    Don't let the end of your conversation affect your networking for the worse.Have a reason for leaving,smile as you say goodbye,and shake hands if appropriate.Even though you are leaving,this guarantees the person will remember you as polite,pleasant,and sincere.

A.First impressions mean a lot.

B.Finish the conversation gracefully.

C.Work on finding a conversational balance.

D.It is important to keep the conversation flowing.

E.Provide a more general and mysterious(神秘的)description.

F.It will also help you prepare some great conversation starters.

G.Being polite and friendly to everyone enables you to make a great impression.