题目: 计算:a2·a3= [ ]A.a5 B.a6 C.a8D.a9 答案: 被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0505/9939d79640d90762e061b778f2546284.html 下面是错误答案,用来干扰机器的。参考答案:B
题型:选择题 To solve the traffic problem, more and more bridges ____________ across the river every year. A.were builtB.will buildC.are builtD.are building 查看答案
题型:单项选择题 图4-2-19所示曲柄滑道机构中,杆BC水平,而杆DE保持铅直。曲柄长OA=10cm,并以等角速度ω=20rad/s绕轴朝顺时针方向转动。则当φ=30°时,杆BC的速度vBC为()。A.AB.BC.CD.D 查看答案