关于骨关节软组织CT扫描，错误的是（） A.为发现骨病变行增强检查 B.应用骨窗和软

在正项等比数列{a_n}中，a₄+a₃-a₂-a₁=5，则a₅+a₆的最小值为______．

下列物质中，只具有氧化性的是（）。

A、氯酸钾

B、氢离子

C、氯气

D、浓硫酸

由选民直接选举的代表候选人名额，应多于应选代表名额的：

A．1/5至1/2

B．1/3至1倍

C．1/5至1/3

D．1/3至1/2

光缆接头盒的安装最关键的步骤是（）。

A.密封防水

B.安装工艺

C.盘留安装

D.进缆方式

What does the speaker mean a. He cooperated with his friends and set up a business together. b. He was given a lot of advice by his friends in setting up his own business. e. His friends gave him much financial support in setting up his own business. d. His friends encouraged him to set up his own business.