低熔点合金熔化时要用清洁()不断搅拌。
A.铁棒
B.铝棒
C.铜棒
D.铅棒
参考答案:A
--___ you got to know my telephone number? ---Through a friend of yours.
A.How was it
B.How was it that
C.Was it how that
D.How did
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