消化性溃疡中巨大溃疡是指（）

A.直径>1.5cm

B.直径>2.5cm

C.直径>2cm

D.深度>0.5cm

E.发生在距幽门2～3cm以内的溃疡

Which is the proper method of determining whether a portable CO₂ fire extinguisher needs recharging?（）

A.Check the tag to see when the extinguisher was last charged

B.Release a small amount of CO₂; if the CO₂ discharges，the extinguisher is acceptable

C.Weigh the extinguisher and compare the weight against that stamped on the valve

D.Recharge the extinguisher at least once each year