经测定，液态BrF3在20℃时导电性很强，说明该化合物在液态时发生了电离，存在阴

5600cm²=______m² 3.2公顷=______m²．

根据句意，用括号中所给单词的正确形式填空，每空一词。

小题1:Many fans felt sad because of the     (lose) of the famous Korean actor.

小题2:Lucy often plays tennis to relax     (she) after school.

小题3:Thanks to these     (science) work, our dream has become true.

小题4:The patient has difficulty     (run) on his own feet.

小题5:We tried to stop the fights, but we knew it was     (hope).

光缆允许弯曲半径大于等于其外径（）倍，施工中允许弯曲半径大于等于其外径（）倍。

A.20；15

B.15；20

C.20；10

D.10；15

什么是元素元素和原子有何联系

关于妊娠性牙龈瘤，错误的是

A．属于血管性牙龈瘤

B．多发生于分娩之后

C．病变血管丰富

D．类似血管瘤

E．纤维性间质可发生水肿或黏液变