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参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】Passage 3 Questions 11 to 15 are based on the following passage: Scientists in India have invented a new way to produce electricity. Their invention does not get its power from oil, coal or other fuel...
A.
Because bullocks have long been used by Indian people
B.
Because bullocks walk slowly and are easy to control.
C.
Because there are few non-working bullocks in India
D.
Because there is not enough oil in India.
【单选题】关于发动机起动机的润滑，以下说法正确的是：（）。
A.
起动机使用发动机的润滑系统进行润滑
B.
因为起动机转动时间短，转速慢，无需润滑
C.
起动机有自己的润滑油箱需单独进行加滑油
D.
起动机使用高压空气的气隙进行润滑，无需滑油