曾经发明创造了数码，堪称古代数学王国，而今电子计算机技术在世界上仍处领先地位的国家是 [ ]
A、中国
B、埃及
C、印度
D、巴比伦
答案：C
为了避免两端电流调节器同时工作引起调节不稳定，逆变侧电流调节器的定值比整流测一般小（）pu。
A.0.5
B.0.4
C.0.2
D.0.1
Most children are interested in amazing things, and they wonder ______.[ ]
A.when can they see UFOs
B.how can elephants walk on tiptoe
C.why do fish sleep with their eyes open
D.why there is no plant life without lightning
