航天飞机只要十个小时就能飞上月球了,载人登月却要花费三天?A space shuttle should take about 10 hours to get to the moon. Why does it take 3 days?

@C Stuart Hardwick的回答

Q: A space shuttle should take about 10 hours to get to the moon.

问:航天飞机只要10个小时就能到达月球。

Incorrect. A space shuttle could never reach the moon, not in a zillion years, not unless it’s carried inside some much larger spacecraft that can reach the moon. Besides, the nice people in the museum won’t let you have their space shuttle.

不正确,航天飞机永远不可能到达月球,数百万年之内也飞不到月球,否则除非它被携带在可以到达月球的更大的航天器中。 等到那时候,博物馆里再好的人也不会让您乘坐航天飞机。

But I digress.

有点离题了。

Q: Why does it take 3 days?

问:为什么去月球需要三天?

You are confusing maximum speed with average speed.

您将最大速度与平均速度混淆了。

Like the space shuttle, the Apollo spacecraft went into low earth orbit at around 17,000 mph. Unlike the shuttle (which was then out of fuel except for what it needed to maneuver and reenter) an Apollo mission still had a nearly full S-IVB upper stage. When that fired, it accelerated itself, the SLA housing the lander, the lander (the LEM), and the Command and Service Modules (the CSM) to about 24,000 mph (11 km/s).

像航天飞机一样,阿波罗号航天器以大约17,000英里/小时的速度进入低地球轨道。 与航天飞机不同(当航天飞机进行机动和再入大气后,就已耗尽燃料),阿波罗飞行任务的S-IVB上层燃料箱仍然几乎满载。 当继续使用这些燃料箱时,它不仅加速了自身,还将装载着着陆器的SLA(The spacecraft-LM adpater),着陆器(LEM)以及命令和服务模块(CSM)的速度提升至约24,000 mph(11 km / s)。

That would indeed be fast enough to reach the moon in ten hours. But as soon as the engine cut off, the spacecraft started slowing down—still under the influence of Earth’s gravity—just as a football starts slowing the instant it leaves the place kicker’s shoe.

那确实足够快,可以在十小时之内到达月球。 但是,一旦发动机熄火,飞船就开始减速(仍然受地球引力的影响),就像足球在离开球员的鞋子的那一刻开始减速一样。

The spacecraft slowed and slowed until it was barely moving (in space terms). By the time it slowed to a mere 2,400 mph, it was close enough to the moon for the moon’s gravity to affect is more strongly than Earth’s, and it started accelerating again, this time toward the moon.

航天器放慢了速度,直到它几乎不动为止(在太空中看了计)。 当它减速到仅2400英里/小时的时候,它已经足够接近月球了,以至于月球的引力比地球的引力要强得多,并且它再次开始加速,这次是向月球移动。

And that’s why it took three days (and will always take three days for a free return trajectory, regardless of spacecraft). The maximum speed at orbital insertion or trans-lunar injection is not the speed for the duration of the flight.

这就是为什么要花三天的时间(无论航天器如何,返回自由轨迹总是要花三天)。 在地球轨道或月球轨道时的最大速度不是从地球往月球航行期间的速度。

All spacecraft are in orbit, all the time. Any spacecraft coasting away from the object it orbits (as in a spacecraft on the translunar coast from the Earth to the moon) is slowed by gravity. Any spacecraft coasting down toward the object it orbits (like a spacecraft on the trans-Earth coast back from the moon) is accelerated by gravity.

所有航天器一直在轨道上运行。 任何想脱离星球控制的航天器(如在从地球到月球的航天器中)都会因重力而减速。 任何想受到星球控制的航天器(如从月球返回的跨地球海岸上的航天器)都会受到重力加速。

I mention free return trajectory because, as a genuine rocket scientist recently explained to me at a conference, we are unlikely to want to send humans to either the moon or Mars on any other kind of trajectory any time in the foreseeable future. A free return trajectory is one that will always take you back home if you just do nothing—useful in case anything goes wrong.

我提到自由返回轨迹是因为,正如一位真正的火箭科学家最近在一次会议上向我解释的那样,我们不太可能希望在可预见的未来,将人类以其他的轨道送入月球或火星上。 就算您什么都不做,那么自由的返回轨迹总是可以带您回家——如果万一出了问题,这很有用。

【评论区】

@ Brian Fitzpatrick

Hey Mr. Hardwick, thats a pretty straightforward answer ya got there, Factual one too, I can say that because I know, I was there…see my family moved to Cocoa, Florida in 1958, when my Father got hired by RCA to be a Photo Mechanic to work on the Cameras that tracked the launches of the rockets at the Cape Canaveral Missile Annex (then it was called the Cape Canaveral Air Force Station as our original “Space Program” was run by the Air Force) we were launching monkeys into space back then…Russia had already launched a dog…(killed it though)…then he became a Photo Specialist when Technicolor took over and NASA came in to being…some of the cameras he mounted on missiles are still in Space and the one he mounted on the Eagle is still on the moon… my father worked at the Space Center until he died of a heart attack in 1971 …I myself worked at KSC doing QC on the Rocket Fuel Trailers from 77 till 80…and do you know that it actually rains inside the VAB…lol

嘿, Hardwick 先生,那是一个很简单的答案,事实上,我也可以说,因为我知道,我在那里……看到我的家人于1958年移居佛罗里达州的可可,当时我父亲被RCA聘为 一位照片机械师,负责跟踪卡纳维拉尔角(当时我们称为“卡纳维拉尔角空军基地”,因为空军最初执行的“太空计划”是由空军执行的)火箭发射的摄像机的,我们正在发射猴子 当时,它已经进入了太空……俄罗斯已经发射了一只狗……(虽然杀死了它)……然后当Technicolor接管NASA并成为美国航空航天局局长时,他成为了照片专家……他安装在导弹上的一些摄像头仍在太空中, 他装在阿波罗11号登月舱上的摄像头上仍在月球上……我父亲曾在太空中心工作直到1971年因心脏病去世……我本人曾在KSC从事从77年到80年的火箭燃料拖车的质量控制工作……你知道吗 实际上在VAB(vechicel assembly building,火箭装配中心)也下雨了……哈哈哈哈

BTW Mr. Hardwick, I read your story “For all Mankind” well written and very interesting…I like the way you got in depth about some stuff and just briefly went into other topics…it kept the story moving…but dang it, I thought maybe somebody like Buck Rogers would come to the girl’s rescue…

顺便说一句, Hardwick 先生,我读了您的故事《 For all Mankind 》写得很好,很有趣……我喜欢您深入了解某些事物的方式,并简要地谈了其他话题……它使故事动起来……但当初,我 以为也许像巴克·罗杰斯(Buck Rogers)这样的人会来救助那个女孩……

I’m not much of a reader, but i would like to check out some more of your stuff, as Space Exploration is a subject I am fond of.

我只是一个读者,但是我想进一步了解您所做的一些事,因为我非常喜欢“太空探索”这个主题。

答主回答:

I’ve often wondered if the “rain inside the VAB” was apocryphal or for real.

我想知道“ VAB内部的雨水”是假的还是真实的。

@ Brian Fitzpatrick

Oh yeah its a fact, since the interior of the VAB in general is not Air Conditioned (certain areas are of course, to protect the sensitivity of the equipment) but the shear mass of the building is so great and with the Florida heat and humidity I have been inside the VAB on bright summer days, and seen it “rain” inside the VAB. What happens is the water vapor condenses on the inside of the roof, and then when it get to be too much it literally rains back down.

哦,当然是真的了,因为VAB的内部通常没有空调(当然,某些区域用于保护设备的灵敏度),但是建筑物的 shear mass 是如此之大, 在灿烂的夏日里,佛罗里达州也受热和潮湿,我一直在VAB内,看到它在VAB内“下雨”。发生的事情是水蒸气凝结在屋顶内部,然后当水蒸气变得过多时,看起来就像是会下雨。

One time when I was in the VAB with the Space Shuttle Atlantis parked in one of the bays. they had to suspend a huge tarp over the Orbiter to protect it from the moisture raining down. On several other occasions when they were rolling a Missile or a Shuttle out to the Launch Pad and we had an afternoon storm pop up, I’ve seen actual rain clouds roll right inside the giant doors and then start pouring down…the place is so big it literally has it’s own atmosphere and even though they have a huge Air Conditioning system (it’s got its own giant building) when they open those huge Bay doors….shoosh there goes all the AC and then the Humidity steams in.

有一次,当我进入VAB时,亚特兰蒂斯号航天飞机停在一个海湾中。他们不得不在轨道器上上悬挂一个巨大的防水布,以保护其免受雨水淋湿的影响。在其他几次情况下,当他们将导弹或航天飞机送往发射台时,天空中又出现了了午后的暴风雨,我看到有朵乌云通过巨大的们进入了VAB内部,然后它就开始下雨了……这个地方是如此大,它可能甚至有自己独特的大气,即使他们有一个巨大的空调系统(它有自己的巨型建筑) 当他们打开各种巨大的舱室门时, …. shoosh 到处都是交流电,然后湿气冒出来。

Inside size is 129,428,000 cubic feet of space, its the largest single-story building in the world at 526 ft tall, its 716 ft long and 518 ft wide, it’s the largest building the World by Volume, and the base of it covers 8 acres. Oh yeah and the 4 doors on the sides, are also the largest doors in the World, at 456 ft tall…ya got to remember the building was designed to Assemble the Saturn 5 missiles…Vertically… and then roll them out to the launch pad…and at 363 ft tall and weighing in at 6,478,000 lbs, they needed some room.

内部面积为129,428,000立方英尺,是世界上最大的单层建筑,高526英尺,长716英尺,宽518英尺,是按体积计算世界上最大的建筑,其基础占地8英亩 。 哦,是的,侧面的4个门也是世界上最大的门,高456英尺。。。要记住,该建筑物的设计目的是组装土星5枚导弹……垂直地……然后将其推出发射场 …身高363英尺,重647.8万磅,他们需要一些空间。

it took me over an hour to walk around it one day

要在里面到处逛逛得花上几个小时。

答主回答:

Too funny: “ actual rain clouds roll right inside the giant doors and then start pouring down” but when you describe it that way, it makes sense. And that close to the ocean, seems like corrosion bust be a constant battle.

太有趣了:“真正的云飘进了巨大的门,然后它就开始下雨了”,但是您这样描述时,这是有道理的。 而且由于靠近海洋,对抗腐蚀似乎是一场持久的战斗。

I have a friend who used to work in space medical for NASA. He was down at the cape when they had three orbiters and kept getting scolded for “touching the shuttle,” to which his reply was “but it’s just THERE.” I’ll have to tell him about the storm clouds.

我有一个朋友曾经为NASA从事太空医学工作。 当他们有三个轨道器时,他在海角坠落,并因“碰到航天飞机”而被责骂,他的回答是“但仅是那里。”我必须告诉他暴风云。【??没看懂】

@ Brian Fitzpatrick

Corrosion and oxidation is a constant enemy when you live near or have a facility so close to the ocean. When I used to live in Cape Canaveral and we had Onshore winds, I use to have to take a hose to my windshield every morning before I would even get in my car, just to rinse off the salt film. A lot of people didn’t do this and it was easy to spot them just by looking at their front windshields (you could see where their wipers had ground the salt into the glass) which really messes ya up as soon as the bright sun reflexed off of it…

当您住在附近或拥有如此靠近海洋的设施时,腐蚀和氧化是永远的敌人。 当我以前住在卡纳维拉尔角(Cape Canaveral)并遇到陆上风时,我常常不得不每天早晨在乘车前,用一根软管把挡风玻璃上的盐膜冲洗掉。 但许多人没有这样做,仅通过观察前挡风玻璃(您可以看到他们的刮水器将盐平撒到了玻璃上)就可以很容易地发现他们,一旦明亮的阳光反射,看起来就非常脏了….

But yeah when I worked for NASA doing QC work on the Rocket Fuel Trailers, we were constantly inspecting EVERYTHING for any sign of degradation and Salt is a very strong corrosive element…I was actually one of those guys like you see in the Movies, walking around with a clipboard, a hand-held lighted microscope and a micrometer wearing the White “Gook Suits” (it’s just what we called them, no relation) they had little booties that were built in to them to cover your shoes, hoods that had a clear face mask, white gloves that snapped “inside out” to your sleeves and a self contained air supply not unlike a scuba diver, so when something was QC tagged (means it passed inspection) YOU better not be touching it…(and if you did, we could certainly get your fingerprints quickly)…

但是,是的,当我在NASA从事火箭燃料拖车的质量控制工作时,我们一直在检查,看是否有任何降解的迹象,而盐是一种很强的腐蚀性元素……我实际上是像在电影中看到的那样的人之一, 他们周围有一个剪贴板,一个手持照明的显微镜和一个千分尺,并穿着白色“ Gook Suits”的千分尺(这只是我们称呼它的方式而已),这内置了一些小罩子可以罩在你的鞋子,有口罩的头罩上,可“内外翻”到袖子上的白手套,以及与潜水员不同的自给式供气系统,因此,当某件物品经过QC标签(意味着已通过检查)时,最好不要触摸它……(如果 您确实做到了,我们当然可以很快得到您的指纹)…

Actually before I jumped up to QC, I worked for PFC (PreFabrication and Cleaning) spray painting the “Bottles” (it’s what we called the 50-100ft long tube like fuel containers that they use to fuel the Missiles). They held the Liquid Nitrogen, Liquid Hydrogen and Liquid Oxygen under high pressure, so they had to be super thick and could not risk having any leaks. We used to undercoat them with Lead Oxide and Zinc Oxide paint…you know “the good stuff” liquid metal…this shit was so toxic that even though we wore respirators with Oxygen pumped in, no one was aloud to be in the paint booth for longer than 40 minutes at a time…I can still remember one time when someone opened a side door and a beam of sunlight shined in and you could literally see the paint floating in the air, it got so thick in there at times that you had to wave your hand back and forth in front of you to be able to see where you were.

实际上,在我进入质量控制之前,我曾为PFC( PreFabrication and Cleaning ,预制和清洁)喷涂“瓶”(这就是我们所谓的50-100英尺长的管子,它们用来为导弹加油的燃料容器)。 他们将液氮,液氢和液氧保持在高压下,因此它们必须超厚并且不能冒任何泄漏的风险。 我们曾经用氧化铅和氧化锌涂料给它们涂底漆……你知道液态金属是 “好东西” ……这种狗屎玩意有毒,即使我们戴着带氧气的呼吸器,也没有人会在油漆间里 一次超过40分钟…我仍然记得有一次,有人打开一扇侧门,一束阳光照进来,您可以从看到漂浮在空气中的油漆,有时油漆变得很浓,您需要来回摇晃你的手驱走它们,您才能看到您究竟在哪儿。

But yeah they have to use really tough stuff to protect everything connected to the Space program.

但是,是的,他们必须使用非常坚固的东西来保护与太空计划相关的所有内容。

Can you see the big gray doors on the right side of the building, theres 2 more on the opposite side too, when they are open and a storm passes by..in comes the rain clouds…remember the doors are 465ft high.

您能看到建筑物右侧的灰色大门吗,对面还有另外2个,当它们打开时,暴风雨经过了……雨云通过门进来了……请记住门高465英尺。

The building itself is an awesome sight to see, and then when you get inside…pffft, its a whole nother story… like a small city…8 acres.

建筑物本身就是一个令人敬畏的景象,然后当您进入建筑物时…pffft,就是另外的故事了…就像一个小城市…8英亩。

@ Steve Leh

Maybe your building is the only one story building that large, but there is a building that IS labeled “World’s Largest Building” is 1 square mile of inside building. It is near Seattle, “the Everett Boeing 777 Plant” which manufactures 4 lines of airplanes all at once inside.

也许您的建筑物是唯一一个这么大的单层建筑物,但是有一栋标榜为“世界上最大建筑物”的建筑物是建筑物内部有1平方英里。它位于西雅图附近的“埃弗里特波音777工厂”,可在内部一次制造4行飞机。

It was built in 1964. Also there is a new building right next to it, identical as 1 square mile. There is a freeway that runs beside them and you can clock it with your car from corner to corner and on the SW corner you will see their built-in air field tower. It does have 2 to 4 stories in its corners for management but all other floors are for airplanes to fit its 4–5 story high planes.

它始建于1964年。旁边还有一栋新建筑,相当于1平方英里。 他们旁边有一条高速公路,汽车随处可见,在西南角,您会看到他们的内置空中塔。 它的角落确实有2到4层用于管理,但其他所有楼层都适合飞机安装4到5层楼高的飞机。

All employees have bikes, scooters, and there are 5 triple-wheel trucks for employees to hop on/off. It’s not for the smokers who need to walk an outside door.

所有员工都有自行车,踏板车,还有5辆三轮卡车供员工上下车。 但这不是为那些需要去门外吸烟的家伙服务的。

It’s right next to its own airport with its own tower where they get their paint, tarmac taxi hours, air-test, as the “cowboy pilots” take off and stop engines and restart engines in the air at only 5000 feet (over our homes) before turn it upside-down over the ocean to stress-test the wings, while 22 technicians work on computers in ejection seats behind the pilot ready to bail. They have on two occasions, once over a desert and once over the ocean. Take a trip to Seattle-Everett on Google.

它就在自己的飞机场旁,带有自己的塔楼,在那里他们可以进行喷漆,停机坪出租车,空气测试,“牛仔飞行员”起飞并停止发动机,并在仅5000英尺的高空重新启动发动机,然后将其上下颠倒翻过海洋以对机翼进行压力测试,而22名技术人员则在飞行员身后准备释放的弹射座椅上的计算机上工作。 他们有两次,一次是在沙漠上,一次是在海洋上。 在Google上前往西雅图-埃弗里特。

@ Brian Fitzpatrick

Hey Steve, yeah I have heard and read about the Boeing Plant out in Seattle, both of them actually, and yeah they are huge too. But what I was saying is that the VAB is the largest single-story building in the world and was also the tallest building (160.3 meters, 526 ft) in Florida until 1974, and it’s still the tallest building in the United States outside an urban area.

嗨,steve,是的,我听说过西雅图的波音工厂,实际上两者都很大。 但是我要说的是,VAB是世界上最大的单层建筑,也是1974年之前佛罗里达州最高的建筑(160.3米,526英尺),它仍然是美国市区外最高的建筑 区域。

And yes there is a actually 2 runways near the VAB, one is for Cargo planes, delivering missile parts and other supplies and then there is also the Shuttle Landing Facility which is like the 17th longest runway in the World at 15,000 ft ( it also has 1,000 ft of usable paved overruns at each end, so it’s really longer than some of the other ones) but it’s where the Space Shuttles use to land at when coming back from Space and some of the Space Shuttle pilots have said that they wish it were longer…

是的,VAB附近实际上有2条跑道,一条是用于货机的,用于运送导弹零件和其他物资,然后还有航天飞机着陆设施,就像世界上第17长的跑道(15,000英尺)一样( 两端均铺有1,000英尺的可用超限铺装,因此它确实比其他一些要长),但这是航天飞机从太空回来时用来降落的地方,一些航天飞机飞行员曾表示希望跑道更长…

Us locals (who worked at KSC) had a nickname for it, we used to call it the “gator tanning facility”, as some of the 4,000 alligators living at Kennedy Space Center, regularly bask in the sun on the runway. You have to remember that KSC is located on Merritt Island, which is also a National Wildlife Refuge and gators are everywhere, mainly because some of the area is swamp like. When my Father 1st stated working out there back in the late 50’s and was mounting cameras on the launch recording towers (they were placed several thousand feet away from the actual Launch pad to record the lift offs) he had to walk thru deep brush and ran into gators and water moccasins all the time.

美国当地人(曾在KSC工作过)有一个昵称,我们过去称其为“鳄鱼晒黑设施”,因为居住在肯尼迪航天中心的4,000只鳄鱼中有一些经常在跑道上晒太阳。 您必须记住,KSC位于梅里特岛(Merritt Island)上,梅里特岛(Merritt Island)也是国家野生动物保护区,而且到处都有鳄鱼,这主要是因为该地区的某些区域像沼泽一样。 当我的父亲第一次说要在50年代后期在那里工作,并将摄像机安装在发射记录塔上时(它们被放置在离实际发射台几千英尺的地方,以记录升空情况),他不得不走过很深的灌木丛并经过有鳄鱼和水蛇的地方。

Back in the 70’s when I worked out there, I personally was late for work more than one time when a gator would decide to sun itself in the middle of one of the access roads. You would try and beep your horn to get them to move (didn’t work most of the time) I even had one bite my tire and dented a front quarter panel when I tried to physically move it out of the way with my car…as I sure as hell was going to be getting out to shoo it away…lol

回到70年代时,我个人上班迟到了不止一次,有一次是因为鳄鱼会决定在其中一条通行道路的中间晒太阳。 您可能会尝试鸣喇叭以使它们移动(大部分时间都不起作用),当我试图用汽车将碰撞它让它离开时,它咬了一口轮胎并弄伤了前四分之一面板… 我地狱在等着那只鳄鱼……哈哈

But yeah there are some bigger buildings than the VAB in the World, but they are all multi-storied.

但是,是的,世界上有一些建筑物比VAB大,但它们都是多层的。

@ Steve Leh

Brian,

A single story building is not a tall building. I’m still not sure where you’re coming from, when saying its the worlds tallest. Also, you really do need to go to Everett, not just Google it. The Boeing building does not have several floors but is 300–400 feet high and is one floor of plane assembly lines. Drive from corner to corner and you will see on your odometer, it is one square mile and is labeled on map and google as Worlds Largest Building, especially in square feet.

单层建筑不是高层建筑。 当说世界最高的时候,我仍然不确定你来自哪里。 另外,您确实需要前往Everett亲自看看,而不仅仅是Google它。 波音公司的大楼没有几层楼,但高300-400英尺,是飞机装配线的一层。 从角落到角落行驶,您会在里程表上看到,它是一平方英里,在地图和Google上被标记为“世界上最大的建筑物”。

The building “floors are actually scaffolding in the corners for supervisor towers. I had lots more to tell you but apparently you are still stuck on your building. I am sure your building is large but not as large is the Boeing structure, which is much larger by far. There are things I wanted to write here but I will make this short. I am not a ‘career writer” especially in Quora which resembles a chat room on AOL.

“建筑物实际上是在主管塔的拐角处的脚手架。 我还有很多要告诉您的,但显然您仍然固执己见。 我敢肯定您的建筑物很大,但却没有波音的大,而波音目前要大得多。 我想在这里写些东西,但我会做简短说明。 我不是“职业作家”,尤其是在Quora中,它类似于AOL上的聊天室。

Brian, how did you get my email address? And how is it that I was not able to reply to your Quora email address? Brian as you did with Stuart, you are arguing with me, and I’m not sure you can see that, because you also can’t see how you are wrong in your arguments. You need to stop and back-peddle a little bud.

Brian ,你怎么得到我的电子邮件地址? 我无法回复您的Quora电子邮件地址怎么办? Brian,你就想和Stuart一样,正在和我讨论,我不确定您能看到这个,因为您也不知道自己的论点错了。 您需要停止自己错误的论点。

@ Brian Fitzpatrick

How do you figure I am arguing with you when I agreed with you about the Boeing Building being the Biggest ? All I was doing was clarifying my original statement about the VAB being the largest “single story” building by Volume. I have never said that the VAB was the Tallest building in the World…although it use to be in Florida at one time and it is still the Tallest building outside an “Urban Area”. Seattle is an “Urban Area” whereas the marshlands of Merritt Island’s Wildlife Refuge is not.

当我同意波音大厦最大时,您会怎么办? 我所做的只是澄清我最初关于VAB是Volume规模最大的“单层”建筑的声明。 我从未说过VAB是世界上最高的建筑……虽然曾经在佛罗里达州,但它仍然是“城市地区”之外的最高建筑。 西雅图是一个“城市地区”,而梅里特岛的野生动物保护区则不是。

Go look up the Vehicle Assembly Building on Wikipedia, I’m sure they will have the facts straight.

请去Wikipedia上的Vehicle Assembly Building查找,我敢肯定他们会讲清楚事实。

Note: Stuart and I haven’t argued about anything and I wasn’t arguing with you. Stuart and I are actually friends, you should read some of his Books, they are great reads.

注意:我和Stuart没有任何争论,也没有与您争论。 我和Stuart实际上是朋友,您应该读一些他的书,这些书很好。

BTW who “Googles” anything anymore ?? they are the worst Tracking, Spyware and Adware website on the Net…try “DuckDuckgo” and all of those Popup Ads will no longer hinder your web surfing.

顺便说一句,谁“谷歌”了吗? 它们是网络上最糟糕的跟踪网站,间谍软件和广告软件网站,请尝试“ DuckDuckgo”,那么弹出广告都将不再阻碍您上网。

“Google it”…..LMAO….that’s so old school…

“Google搜索?”….我快笑死了….这早就过时了。

【博主吐槽:逐渐忘记标题….不过这些有关火箭组装发射的故事看起来还是挺有意思的,也能看一下别人对于问题的不同看法】


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