A:apology
B:excuse
C:impression
①写作业 ②睡觉
如图所示,光滑轨道的半径为2 m,C点为圆心正下方的点,A、B两点与C点相距分别为6 cm与2 cm,a、b两小球分别从A、B两点由静止同时释放,则两小球相碰的位置是( )
The computer company just released an ____ (更新) version last week, and it'll be used in over 50 local classrooms this coming school year.