nối 2 ròng rọc dộng và 1 dòng dọc cố định thành 1palang thì hệ thống sẽ nâng vật nặng cho ta lợi bao nhiêu lần về lực tại sao

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1.tìm từ khác với từ còn lại. 1, a, village b, flat c, house d,hotel 2. a, fever b,matter c,sore throat d,toothache 3.a,did b,had c, play d,went 4.a,small b,quiet c,like d,far 5..a,train b,underground c,motorbike d,countryside 6.a,may b,jump c,ride d,run 7.a,train b,motorbike c,coach d,hometown 8.a,toothache b,arm c,headache d,earache 9.a,played b,ate c,swam d,went 10.a,wait b,intelligent c,clever d,kind 11.a,stadium b,writer c,museum d,post office 12.a,snowy b,cool c,foggy d,banana 13.a,wonderful b,beautiful c,interest d,attractive 14.a,museum b,pagoda c,park d,history 15.a,more b,like c,visit d,think 16.a,city b,village c,town d,place 17.a, kind b,greedy c,gentle d,order 18.a,winter b,season c,autumn d,spring 2.điền từ còn thiếu : 1.i have a pain in my stomach.i have a...... 2.don't......the stove! you may get a burn. 3. what do you do in your free time? - i......camping with my friends. 4.what....in the story? 5.what do you think of mai an tiem? he's.... ; a, stupid b,gentle c,hard-working d,greedy 6,....would you like to be in the future? 7,i'd like to...patients. 8,the post office is......the cinema and the supermaket. 9,what would you like to drink? ; a,orange b,bread c,milk d,fish 10,how...seasons are there in a year? 11,i have a...i have a pain in my tooth. 12,you...carry havy things. 13,i usually...swimming in my free time. 14,what...in the story? 15,what do you think of the older brother?; it's.... (người anh trong câu truyện cây khế ) 16,what would you like to....in the future? 17,i would like to...patients. 18,the cinema is....the bus stop 1 and bus stop 2. a,on b,in c,next to d,between 19,why would you like to be an...? a,nurse b,architect c,writer d,teacher 20,i went to hue by... a,car b, the fox c,modern d,clever 21,i'd like to...patients.