WhichtwostatementsaretrueaboutBPDUport-guardandBPDUfiltering?()
A. BPDUport-guardcanbeenabledglobally,whereasBPDUfilteringmustbeenabledonaper-interfacebasis.
B. Whengloballyenabled,BPDUport-guardandBPDUfilteringapplyonlytoPortFastenabledports.
C. Whengloballyenabled,BPDUport-guardandBPDUfilteringapplyonlytotrunking-enabledports.
D. WhenaBPDUisreceivedonaBPDUport-guardenabledport,theinterfacegoesintotheerr-disabledstate.
E. WhenaBPDUisreceivedonaBPDUfilteringenabledport,theinterfacegoesintotheerr-disabledstate.
F. WhenaBPDUisreceivedonaBPDUfilteringenabledport,theinterfacegoesintotheSTPblockingstate.
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屋面工程是容易产生亏损的工程,材料员要做好屋面工程施工的检查工作,以防止高标号水泥代替低标号水泥,以水泥砂浆代替混合砂浆,以免增加亏损。()
油发实质上是食品膨化技术在于制原料涨发中的应用。()