363 If a petrol engine discharges black exhaust, it means
(A) the petrol is being completely combusted.
(B) the petrol is not being completely combusted.
(C) The oil is being combusted.
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統計: A(0), B(2), C(1), D(0), E(0) #2214824
統計: A(0), B(2), C(1), D(0), E(0) #2214824