On what does the efficiency of a nation depend?A．Every individual.B．Its machines.C．Its wea

What does the cancellation of the 16－day flight mean？A．The scientists on the ground are pu

What kind of information does the man read about？A．A discount on computer monitorsB．A sale

What is the purpose of sub cooling R－12 in the condenser？ .A.to increase the system effici

What does the passage mainly discuss？A．The purchase of followers.B．The research on Twitter

What does the Hong Kong government call on its people to do？A．To know the agenda of the co

What does the doctor give Jessica on the day of their meeting？A．Some medicine for her stom