It's convenient to own a car; however,I

下列CT影像中，最支持胰腺癌诊断的是（）

A.胆管扩张明显，胆总管下端可见2cm×1cm的极强密度区

B.胰头有3cm×4cm不均匀低密度区，强化后有不均匀增强

C.胰头均匀低密度区，CT值10HU，不被强化，胰体尾萎缩，胰管扩张

D.胰头部增大，密度与其他部位胰腺组织密度一致，胰周界限模糊

E.胰周及腹腔渗出，胰腺实质内有不规则低密度区，强化后低密度区增强不明显

双母线事故应尽快恢复一条母线送电，可用（）或（）等方法试送。

People often wonder why they have spend so much money at the supermarket, and often on things they didn’t intend to buy in the first place. A recent survey indicates that 75% of all grocery shoppers make at least one impulse buying. They may be attracted by eye-catching display, or colorful package. For those shoppers, there is a simple way of avoiding impulse buying, and saving money on groceries. That is, they should make a shopping list beforehand, and stick to it.

影响产品质量的异常因素，其特点是______。

A．容易发现和消除

B．难以消除

C．不值得消除

D．生产过程所固有

制氢室和机组的供氢站应采用（）型电气装置。并采用木制门窗，门应（）开，室外还应装防雷装置。