题干

如图,关于声音的四幅图片的说明,正确的是(  )

A:图片a中的蝙蝠利用发出的电磁波导航

B:图片b表明月球上的宇航员能直接交谈

C:图片c所示的隔音墙表明噪声可以在声源处减弱

D:图片d表示声音是由发声体的振动产生的

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答案(点此获取答案解析)

D

同类题4

阅读下面短文, 掌握大意, 然后从每题所给的A、B、C、D四个选项中选出最佳选项.

    Andy woke up and looked at the clock 11: 30? He jumped out of bed and threw on clothes. He had wanted to get up early and surprise his dad with Father's Day breakfast in bed﹣with his mom's help of course. He took up the wrapped present on his desk and went to find his 1.

    "Where is Dad?" Andy checked all the rooms, but the whole house was empty. He walked out to the 2, and his jaw dropped. Dad was holding a hammer and looking at a new tree fort that stood in 3 big back yard.

    Andy climbed the rope ladder up to the fort. It had two rooms with three small windows.

    Dad followed Andy into the fort, looking excited. "I spent all morning 4 it. I had one when I was your age. Grandpa surprised me with it on Father's Day, too. "

    "So, it's like a(n) 5?" Andy asked.

    "Yes, this is a present for 6 of us. Maybe you'll build one for your son one day. "

    Dad looked around and asked Andy 7 they would do first in the tree fort. Andy slowly showed the 8 and said, "Happy Father's Day!" He didn't think it was possible, 9 Dad's smile widened as he opened the gift. "A chess set! How did you know I wanted 10?" Andy always saw his dad playing against the computer and he guessed it 11 be his father's favorite.

    "Let's play it!" Dad set up the chessboard. "It's the 12 gift I got of all this Father's Day. "

"I'm glad you like it." Andy said.

    "I do, but I was talking about spending more time with you. I 13 loved the father﹣son time. I spent a lot with your grandfather when I was 14. "

    Andy looked at his dad. "Can we call Grandpa and 15 him to come to the fort?"

Dad squeezed Andy's shoulder. "I think he'd love that."

    That day, the three men played, talked and laughed. It was really a happy Father's Day.

同类题5

阅读下面文章,完成下列各题。

《父亲给我的负荷》
若干年后的今天,我依然记得那些晦涩难挨的日子。在那些日子里,父亲给了我终身难以卸去的精神负荷。   1996年夏天的中考,我没考上县一中,以7分之差失去了上重点高中的资格,但我那不争气的分数上普高还是绰绰有余的,所以我还是有考大学的机会。
“四中一年难得考几个人,读也是白交钱,还是不读吧?”看着分数条,父亲皱着眉头说。
我低着头说:“我想考大学,不读高中怎么行呢?”
“你连一中都考不上,还考什么大学?”父亲似乎有点不耐烦。
“后村铁匠家的二毛就是从四中考上的。”
“二毛?他复读了三年,等他考上的时候铁匠的背都驼了。”父亲显然不习惯我的顶嘴,加大了音量……
就这样,我开始了在黄土地上和泥巴田里的劳作。然而,繁重的农业劳动毕竟还是使我背惯书包的肩膀不胜负荷。随着九月的临近,我对教室和书本的渴望也日益膨胀,就硬着头皮向父亲提出了我要去读书。父亲举着烟斗,眯着眼“吧嗒”一声抽了一口,然后喷着烟雾说:“有史以来,我们村就没出过举人,秀才也少,风水不好,加上你读书又不中,考大学就莫作指望了。”
我不知道一向通情达理的父亲为什么在这件事上突然生硬和固执了,但我已感觉到凭我的力量是无法撼动他的。后来找来姑妈、二叔跟父亲求情,可父亲态度依然强硬。
父亲并不为所动,冷冷地说:“他要是总考不上呢,你总不会修造一所大学让他读吧?”气得姑妈晚饭没吃就拂袖而去。
随着姑妈的离去,我看到我最后一丝希望也随着屋外的清风飞向天际那缥缈而遥不可及的云端。坐在屋后的荷塘边,我脑中一片空白,完了,我不可能有上大学的机会了。别了,大学梦!A.夕阳已西去,在天边留下一抹血红的残霞,远山如黛,近荷似玉,却给人一种闷闷的感觉。
父亲这时候出现了,他倒提着烟斗向我走来。“天将降大任于是人也,必先苦其心志,劳其……”他口中喃喃地念道。我不知道他是什么意思,终于忍不住地在沉默中爆发了,站起来冲他喊道:“我要读书!不让我读书我会让你后悔一生的!”然后静静地等着他手中的烟斗雨点般向我袭来。谁知,父亲没有打我,很亲切很满意地笑了,“好,有种!想读书是好事,你到处找人,我就知道你憋了一股子劲想读书,用这股劲读书还怕读不出来吗?学费早就准备好了,以后不管你读到哪里,我就是挣断肋骨也要供你……”说着说着,父亲竟有些哽咽了,眼圈也有些发红。
而我,则幸福得泪流满面,原来他一直在用心良苦地激发我的斗志。
三年后,我如愿以偿,考上了大学。B.依然是在夕阳西下时,绚丽的晚霞映红了半边天,满塘绿荷摇曳,清香沁人,在习习凉风中,将通知书递给父亲时我不禁眼圈红了,而父亲则幸福得泪流满面。