如图，质量为m的物体A与水平面间的滑动摩擦因数为μ，受到一与水平方向夹角为的恒力F作用，物体的水平加速度为()
Iwouldverymuch______tovisitsomeoftheplacesthatIhavebeenreadingabout.
Weallknowaboutthe_____thatsmokingcandotoourhealth.
Inmyopinion,theyshoulddosomethingtorewardtheirmost_(produce)employees
两列机械波I、II在传播过程中遇到一障碍物，I的波长与障碍物尺寸相当，II的波长远小于障碍物尺寸，则机械波（）
