( )是12的质因数.
A.1
B.2
C.4
D.12
12=2×2×3,
质数有2、3,即2、3是12的质因数;
故选:B.
________I’m concerned, we are going to take an exam in a month.
A.As long as
B.As far as
C.Just as
D.Even if
互感器、避雷器安装,运输、放置、安装、就位应按产品技术要求执行,期间应防止倾倒或()。