英语翻译(A)Greek soldier sent messages by turning their shields

英语翻译
(A)
Greek soldier sent messages by turning their shields yoward the sun.The flashes reflected light could be seen several miles away.The enemy did not know what flashe meant,but other Greek soliers could understand the messages.
Roman soldiers in some places built long rows of signal towers.When they had a message to send,the soldiers shouted it from tower to tower.If there were enough towers and enough soldiers with loud voices,important news could be sent quikly over distance.
In Africa,people learned to send messages by beating on a series of large drums.Each drum was kept within hearing distance of the next one.The drum beats were sent out in a special way that all the drummers understood.Though the messages were simple,they could be sent at great speed for hunders of miles.
In the eighteenth century,a French engineer found a new way to send short messages.In this way,a person held a flag in each hand and the arms were moved to various positions representing different letters of the alphabet.It was like spelling out words with flags and arms.
Over a long period of time,people sent messages by all these different ways.However,not until the telephone was invented in America in the nineteenth century could people send speech sounds over a great distance in just a few seconds.
(B)
Because we can feel that things are heavy,we think of weight as being a fixed quality in an object,but it is not really fixed at all.If you could take a one pound packet of butter 4000miles out from the earth,it would weigh only a quarter of a pound.
Why would things weigh only a qurter as much as they do at the surface of the earth if we took them 4000miles out into space?The reson is this:All object have a natural attraction for all other object;this is called gravitational attration,but this power of attraction between two objects gets weaker as they get farther apart.When the butter was at the surface of the earth,it was 4000 miles from the centre(in other words the radius of the earth is 4000miles).When we took the butter 4000 miles out,it was 8000 miles from the centre,which is twice the distance.
If you double the distance between two objects,their gravitational attraction decreases two times two.If you treble the distance,it gets nine times weaker(three times three).If you take it four times as far away,it gets sixteen times weaker(four times four)and so on.

这么长,还没有分,虽然没有分,还是帮你一下吧.
A.
希腊的士兵靠将盾牌指向太阳来传递信息.太阳在盾牌上反的光能在几公里外被看到.敌人并不知道射出来的光线是什么意思,但是其他希腊的士兵却能读懂其中的含义.
罗马的士兵在某些地方会修建一长排的信号塔.当他们需要向外发送信息时,士兵们就会靠大声呼喊的方式,从一个塔传到另一个塔.如果有足够的塔和足够的大嗓门的士兵,重要的信息就很快会被传到远处.
在非洲,人们学着用敲一连串的大鼓的方式来发送信息.每个鼓之间的距离都在能听到对方的声音之内.鼓点是以一种特殊的方式传送的,所有敲鼓的人都明白其中的意思.虽然所传的信息很简单,但他们却能以最佳的速度传到几百里外.
在18世纪,一个法国的工程师发现了一个新的方式来传递短信息.这种方式中,一人双手举着一个旗帜,然后士兵们移到各处代表不同的字母.就好象是通过旗帜和士兵来拼出文字.
再过了很长一段时间,人们通过所有这些不同的方式来传递信息.然而,直到19世纪电话在美国发明后人们才能够在几秒内将语音信息发到很远的地方.
(B)
因为我们能够感觉到某些东西很重,因此我们将重量作为实别某个事物的固定量,但实际上它根本不是固定的.如果你能将一个一磅重的黄油包裹带到距地面4000英里以外的地方,它的重量将变为1/4磅重.
为什么物品被带到4000英里以外的太空它的重量就变成了在地面时和重量的1/4了呢?原因是这样的：相对于其它物体,所有的物体都有一个自然引力,这被称作重力,但是在两个物体之间的距离越来越远时,这种引力就会变得越来越弱.当黄油在地面上时,它离中心点是4000英里（换句话说,地球的半径是4000英里）.当我们把黄油拿到4000英里以外,它离中心就是8000英里了,是两倍的距离.
如果将两个物体的距离拉长到两倍,他们的重力就减少了2X2倍.如果你将距离拉长三倍,就减少了9倍（3X3倍）.如果你将距离拉长到4倍那么远,它就减少了16倍（4X4倍）,以此类推.