关于硬膜外隙的描述，错误的是（）。

A.位于椎管内壁与硬脊膜之间

B.内有脂肪、椎内静脉丛、淋巴管、脊神经根等

C.上端起自枕骨大孔

D.下端终于第2骶椎高度

E.总容量约为100ml

. — Do you think there is anything ____ interest in the exhibition?

— Yes, I think some of the pictures are ____.

A．for; of help

B．of; of great help

C．in; of helpful

D．at; helpful