In slow speed two-stroke engines, the fresh air entering begins when and stops as .A.the i

In slow speed two-stroke engines, the fresh air entering begins when and stops as .

A.the inlet port is opened by the up coming piston; the port is closed by the down going

B.the inlet valve is opened by the down going piston; the inlet valve is closed

C.the inlet port is opened by the down going piston; the port is closed by the up coming

D.the inlet valve is opened

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