题干

由7个百和4个十组成的数是____.
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740

同类题1

阅读《社戏》选段,完成小题。
        我的很重的心忽而轻松了,身体也似乎舒展到说不出的大。一出门,便望见月下的平桥内泊着一只白篷的航船,大家跳下船,双喜拔前篙,阿发拔后篙,年幼的都陪我坐在舱中,较大的聚在船尾。母亲送出来吩咐“要小心”的时候,我们已经点开船,在桥石上一磕,退后几尺,即又上前出了桥。于是架起两支橹,一支两人,一里一换,有说笑的,有嚷的,夹着潺潺的船头激水的声音,在左右都是碧绿的豆麦田地的河流中,飞一般径向赵庄前进了。
        两岸的豆麦和河底的水草所发散出来的清香,夹杂在水气中扑面的吹来;月色便朦胧在这水气里。淡黑的起伏的连山,仿佛是踊跃的铁的兽脊似的,都远远地向船尾跑去了,但我却还以为船慢。他们换了四回手,渐望见依稀的赵庄,而且似乎听到歌吹了,还有几点火,料想便是戏台,但或者也许是渔火。
那声音大概是横笛,宛转,悠扬,使我的心也沉静,然而又自失起来,觉得要和他弥散在含着豆麦蕴藻之香的夜气里。
        那火接近了,果然是渔火,我才记得先前望见的也不是赵庄。那是正对船头的一丛松柏林,我去年也曾经去游玩过,还看见破的石马倒在地下,一个石羊蹲着在草里呢。过了那林,船便弯进了叉港,于是赵庄便真在眼前了。

同类题5

阅读理解

    See a cell phone cover that you like on Taobao? Forget about placing an order, paying the bill online and waiting for days for it to be delivered to you. In the near future, you'll be able to get it in minutes just by hitting "print" on your computer. You might find it hard to believe that you could actually "print" an object as you would a picture. But it is not that hard to understand how it would work. Just as a traditional printer sprays (喷) ink onto paper line by line, modem 3-D printers spread material onto a surface layer by layer, from the bottom to the top, gradually building up a shape.

    Instead of ink, the materials the 3-D printer uses are mainly plastic, resin (树脂) and certain metals. The thinner each layer is — from a millimeter to less than the width of a hair —the smoother and finer the object will be. This may sound like a completely new technology, but the truth is that 3-D printing has been around since the late 1980s. Back then, it was barely affordable for most people, so few knew about it.

    Last year, though, saw a big change in the 3-D printing industry — printers became much cheaper. For example, 10 years ago a desktop 3-D printer might have cost £20,000, while now they cost only about £ 1,000, according to the BBC. Taken out of the factory and introduced to more diverse and common uses, 3-D printing can create just about anything you can think of --- flutes (笛子), bikinis, jewelry, aircraft parts and even human organs. In fact, scientists from Cornell University in New York have just made an artificial ear using a 3-D printer, according to Science Daily. The fake ear looks and acts exactly like a natural one.

    However, as 3-D printing becomes more common, it may bring about certain problems —such as piracy. "Once you can download a coffee maker, or print out a new set of kitchen utensils (餐具) on your personal 3-D printer, who will visit a retail (零售的) store again?", an expert in 3-D printing told Forbes News. Even more frightening, what if anyone in the world could use a 3-D printer to print out a fully functioning gun?