A．they operate between 150 and 450 rpm
B．they are connected to the propeller by gearing
C．their smaller size and weight
D．they can be connected directly to the propeller without gearing
People now have more leisure time, which is the reason why the demand for servic
Why is it that the more connected we get， the more disconnected I feel？ Every ad
[试题]4.Why is the conquest of space more than a great a［A］Becauseitisfullofchallengesforhumanbeings.［B］Becauseitmaybenecessaryforhumanbeingstosurvive.［C］Becauseitisthegreatestadventureinhumanhistory.［D］Becauseitismoreexcitingthananyotheradventures.
Why can we see more Chinese elements in foreign movies?()A. If they want to ente
[单选题]Why didn't Peter take more money from the bank?A．He was afraid that be would be caught on the spot.B．The maximum sum allowed was ＄5,000.C．He was limited by time and the size of his pockets.D．Large bills were not within his reach.
Theres a reason fire squads battling more frequent blazes in Southern California
That is, it seems to be everywhere. Yet what does it all mean? Why are people mo
[单选题]（ ）More and more waste has __________ a lot of space.We should do something to reduce it.A．taken placeB．taken awayC．taken upD．taken off
B. More and more Chinese people can hardly live without their phones nowadays
[单选题]More and more young people are trying to do something _____ the old.A． served B. to serve C. serve D. serves