题目内容
两拉杆的材料和所受拉力都相同，且均处在弹性范围内，若两杆长度相等，横截面面积A1＞A2，则（）。
查看答案
搜索结果不匹配？点我反馈
更多问题
A.saidB.1aidC.gainD.pain
The writer suggests that，when one hasn’t caught the name of a stranger，he should________
完成下列各选项 通读下面的短文，掌握其大意。然后，从每小题的四个选择项中选出可填入相应空白处的最佳选择，并把它前面的大写字母填人左边的括号里。 Some people think they have an answer to the problem of car crowding and，pollution in large cities．Their 21________ is the bicycle，or bike．In a great 22________ cities，hundreds of people ride bicycles to work every day．In New York City，some bike riders have been formed a group 23________ Bike for a Better City．They claim that if more people Me bicycles to work，there 24________ be fewer ears in the downtown section(闹市区)of the city and 25________ 1ess dirty air from car engines．For several years this 26 ________has been trying to get the city government 27________ bicycle riders．For 28________，they want the city to paint special lanes(narrow，often winding roads or ways)for bicycle only on some of the main streets，because when bicycle riders must use the 29________lanes as cars，there may,be 30________．Bike for a Better City feels that if there were 31________ lanes，more people would．use bikes．But no bicycle,lanes hove：been 32________ yet． 33________ thinks they are a good idea．Taxi drivers don’t like the idea--they say it will slow transport。Some store owners on the main streets don’t like the idea--they，say that if there is less traffic，they will have less 34________．And most people live 35________ far from downtown to travel by bike．
函数f(x)=(x-1)(x-3)的最小值是（） (A)-4 (B)-3 (C)-1 (D)0
微信支付 
支付宝支付