【单选题】Food packages, bottles and tins for drinks can cause ______.
A.
air and water pollution
B.
both a litter problem and a waste of resources
C.
to pay for the service
D.
to produce the receipt
【判断题】the ralative value of electrode potential can bot be measured.
【单选题】Each guest here can have a drink. They can choose ________ a hot drink ________ a cold one. [ ]
【单选题】What can be inferred about the irony mentioned in Paragraph 3?
A.
Scientists and thieves both opened the coffins.
B.
Only clever people could be this type of thief.
C.
Nobody wants to be a thief but is forced to sometimes.
D.
This kind of thief is respected by some people.
【单选题】Job sharing is popular with young mothers mainly because______.
A.
they can take care of both work and family
B.
they are over ideal working ages
C.
they seek equal opportunities with men
D.
they have difficulty finding full-time jobs
【判断题】the relative value of electrode potential can bot be measured.
【判断题】the absolute value of electrode potential can bot be measured.
【简答题】振动和波动有什么区别和联系?平面简谐动方程和简谐振动方程有什么不同?又有什么联系?振动曲线和波形曲线有什么不同?行波和驻波有何区别?