题干

单位向量的夹角为,则

A:

B:  

C:   

D:

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B

同类题1

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    Ways to Host an Eco-Friendly Cookout

    Eating in the open air may feel eco-friendly, but outdoor dining can result in unnecessary waste if you aren't careful.____If you keep that in mind throughout your preparations, you'll be off to a good start.

Reduce, Reuse, Recycle

    Skip the paper invitations and use online services like Email, or Facebook events____This way you'll avoid ending up with five different potato salads that go uneaten. Make it easy for guests to sort garbage by positioning different trashcans in a central location: one for kitchen garbage, one for recyclables, and one for non-recyclables.

Stop Using Plastic

    Plastic is a leading cause of litter and isn't easy to recycle. To make sure your cookout eco-friendly, consider some other options for making your cookout stand out. Use recycled jars as glasses. They're also far less breakable than regular glasses____ If guests know which glass is theirs, they don't need to reach for another one, which cuts down on the cleanup you'll be doing.

____

    Wherever possible, shop for local produce and goods to serve your guests. This will reduce your carbon footprint and help support your local economy. Buy produce and meats at your local farmers' market. Look for organic, but favor local over organic if you have to make a choice.

Use Renewable Light Sources

    ____ As the sun goes down, illuminate your party space with LED lighting and solar- powered decorations. Invest in some citronella (香茅精油) candles and torches to help drive away insects naturally.

A. Support Global Economy

B. Think Globally, Shop Locally

C. Ask guests to bring glasses of their own

D. Keep track of what everyone is bringing ahead of time

E. Save on energy by hosting your party during the daylight hours

F. One of the keys to being green is to reduce waste wherever possible

G. Put up some labels to the jars so people can write their names on them

同类题2

阅读下面两段文言文,完成小题。
         【甲】晏子至,楚王赐晏子酒。酒酣,吏二人缚一人诣王。王曰:“缚者曷为者也?”对曰:“齐人也,坐盗。”王视晏子曰:“齐人固善盗乎?”晏子避席对曰:“婴闻之,橘生淮南则为橘,生于淮北则为枳,叶徒相似,其实味不同。所以然者何?水土异也。今民生长于齐不盗,入楚则盗,得无楚之水土使民善盗耶?”
                                                                                                                                                                          (《晏子春秋》)
        【乙】景公游于寿宫,睹长年负薪者,而有饥色。公悲之,喟然叹曰:“令吏养之!”晏子曰:“臣闻之,乐贤而哀不肖,守国之本也君爱老而恩无所不逮①治国之本也。”公笑,有喜色。晏子曰:“圣王见贤以乐贤,见不肖以哀不肖。今请求老弱之不养,鳏寡②之无室者,论而共秩焉。”公曰:“诺。”于是老弱有养,鳏寡有室。
                                                                                                                                                                             (《晏子春秋》)
注释:①逮:到。②鳏寡:老而无偶的男女。