it travels 300000km a second是什么意思

it travels 300000km a second是什么意思 It travels at 1,020km per hour the()thing in the universe is light,it travels at 300000 km per secondfaster 还是 fastest啊? 解一道英语阅读题：where:the trip starts in the aoraki/mt.cook national park,about 50km south in adirect line from mt.cook.it then travels about 60 km down to meet the haast river,about 50 km south of haast,and about 120 km from wanaka.为什 it travels all day and all night（翻译） it travels 300,000 kilometres a second是什么意思 It travels very slowly .对very slowly提问____ does it travel? 连词成句（英语——初一）second、speed、a、of、300,000km、light、per、travels、at 一道天体物理的题,实在想不出来了,(2) The Canadian Space Agency gives you a second assignment.A satellite is in circular orbit around Mercury.It travels at a distance of 124 km above the surface of Mercury and its period of rotation is 1 A blimp travels 2 hours with the wind and 5 hours against it It ( )that light travels faster than soundA.believe B.believed C.is believed速度 It is known to all that light travels in straight lines. 怎么改成强调句 The moon travels round the earth,it is our _____________.填一个词 It's_common knowledge that light travels faster than soundA.a B.an C.the D/ Light travels at a speed which is about a million times faster than the speed of sound.In one second,light travels about 300,000km.But sound travels only 344m.You can get some idea of this difference by watching the start of a race.If you stand some many people ___ around the world thinke it's necessary toa.travel b.travels c.traveling d.travelled a man travels the world over in search of what he needs and returns home to find it的中文 Summer usually___ from June to August.It is a good season for surfing. A lasts B ends C takesD travels