【单选题】要选定多个不连续的文件(文件夹)要先按住( ),再选定文件
【单选题】In tire traction rating, which one stands for the top of the scale?
【判断题】当系统中的未知力数目多于独立平衡方程的数目时,未知力就不能全部由平衡方程求出,这样的问题称为静不定问题或超静定问题。
【简答题】A skidding wheel (where the tire contact patch is sliding relative to the road) has less traction than a non-skidding wheel.