what is a coaster used for?

what is a coaster used for? what high speed the coaster is moving at 后为什么加at 英语：那个ch发音是不同的?A.chopsticks B.children C.school选择正确答案.1.There ( )be a roller coaster.A:wont’t B:is C:are 2.What ( )a garden? A:about B:at C:did A c— tells us what time it is. what pains us trains us.a smile is the most charming part of a person forever The big hill on a roller coaster ride is 91.0m high.If the mass of the roller coaster and its two riders is 314.0kg and the maximum velocity reached by this roller coaster ride is 28.0 m/s,how much Kinetic Energy is lost in the system? —can you tell us---?—he is a tour guide.A、what is your fatherB.how is your fatherC.what your father is likeD.what yourfather is It is true___he said surprised us all A.what B.that C.that what D.what that All ___ the teacher has told us is very important to us.A.what B.which C.why D.thatAll ___ the teacher has told us is very important to us.A.what B.which C.why D.that 有图 求真相.Suppose the roller coaster in Fig.6-38 (h1 = 37 m,h2 = 12 m,h3 = 20) passes point A with a speed of 1.20 m/s.If the average force of friction is equal to one third of its weight,with what speed will it reach point The distance travel Happiness is what you say with us 想买这个产品.但文字是英文.是啥意思.能翻译下吗2014 The Mouse House Family maze, the mouse family is maze crazy! What a great way to develop motor skills, enjoy stacking, and mazes. Includes magnetic stacking mouse, 3 track coaster ______ useful the information they've given to us is A what B what a C how the D how 1.___ is known to us all is that China is a developing country.A.Which B.what C.as D.1.___ is known to us all is that China is a developing country.A.Which B.what C.as D.It2.___ is known to us that China is a developing country.A.Which B.As C.What D. __________tell us what something is like.（根据词义写出单词,开头字母是A） All-----they have done is good for us A What B which C why D / it is teamwork ___keeps us alive.A what B which C that D who the stories they tell us reveal what i'm convinced is a new window on animal