培养基(culturemedium)
由壳体、全封闸板、阀座、丝杠等组成的封井器称为()。 ["A、自封封井器","B、半封封井器","C、全封封井器","D、两用轻便封井器"]
纯培养物(pureculture)
由壳体、半封芯子总成和螺纹等组成的封井器称为()。 ["A.自封封井器","B.半封封井器","C.全封封井器","D.两用轻便封井器"]
用拉线法指示巷道掘进()米后,应检查和延设中线。 ["20-30","30-40","40-50","50-60"]
平皿(Petri dish)