题型:问答题 简答题 可利用同一化学原理解释现象的是 (填序号)①久置的石灰水液面上出现一层硬壳状薄膜;②向澄清石灰水中,通过吸管不断吹入由人体呼出的气体后,石灰水变浑浊;③为使石灰浆刷过的墙壁快点干燥,在室内生一盆炭火,开始时墙壁反而潮湿;④向紫色石蕊试液是通入CO2气体,试液变红色。 查看答案
题型:问答题 简答题 如图4-37所示点P沿螺线自外向内运动。它走过的弧长与时间的一次方成正比。关于该点的运动,有以下4种答案,请判断哪一个答案是正确的()。A.速度越来越快B.速度越来越慢C.加速度越来越大D.加速度越来越小 查看答案
题型:问答题 简答题 Questions 14-18 ·Using the information in the text, complete each sentence 14-18, with a word or phrase from the list below. ·For each sentence (14-18), mark one letter (A-G) on the Answer Sheet. ·Do not mark any letter twice.A. $150B. safeC. agreementsD. drivers who can’t drive on because of the flat tireE. a flat tireF. provide a kind of temporary support to the flat tireG. more than $150According to the passage, Quickwheel is a tool that can be used to replace ______. 查看答案