A circuit breaker and a fuse have a basic similarity(类似) in that they both ______.
A. can be reset to energize the circuit
B. should open the circuit when overloaded
C. will burn out when an over current flow develops
D. should short the circuit when overloaded
What type of valve is used to direct the flow of hydraulic fluid？
A. relief valve
B. direction control valve
C. stop valve
D. pressure control valve
几何学可以让人领会到不以人们意志为转移的、外在的、客观的逻辑。()
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