— I think l will tell you the phone then.
A:in
B:on
C:at
D:of
如图所示,竖直平面内放一直角圆杆AOB,水平和竖直的杆上各有质量均为m的小球A和B套在上面(球中心孔径比圆杆直径大些),A、B间用不可伸长、长度为l的轻绳相连,已知竖直杆光滑而水平杆粗糙,绳子与竖直杆间的夹角为θ.当θ=37°时A球恰好静止.现用一水平力F向右拉A球,使A球缓慢运动至θ=53°处,设最大静摩擦力等于滑动摩擦力,重力加速度为g,sin37°=0.6,cos37°=0.8.则( )
若函数f(x)=logax2-ax+12有最小值,则实数a的取值范围是____
Unlike a film, __________ a passive audience watches and hears __________ is happening on the screen, Real Cine puts you into the action and connects with your senses of sight, smell and touch in an active way.
①实现国家独立自主 ②实现人民当家做主
③成为现代化强国 ④确立社会主义制度