营业前应检查人员着装仪表,放好(),做到仪容仪表清洁整齐。
A、手机
B、钥匙
C、钱包
D、个人财物
参考答案:D
A、B两物块置于光滑水平面上,并用弹簧相连,如图所示。当压缩弹簧后无初速地释放,释放后系统的动能和动量分别用T、p表示,则有:()
A.T≠0,p=0
B.T=0,p≠0
C.T=0,p=0
D.T≠0,p≠0
Excuse me, how far is the airport from here? ()
A.You can take a taxi.
B.It‘s about thirty miles.
C.I‘ll fly to Sidney.
D.It‘s only six hundred dollars.