对存在或曾经存在传染源的场所进行的消毒称为()
A.疫源地消毒
B.预防性消毒
C.随时消毒
D.终末消毒
E.环境消毒
参考答案:A
如图所示,平行板电容器的两极板A、B接于电池两极,一带正电的小球悬挂在电容器内部,闭合S,电容器充电,这时悬线偏离竖直方向的夹角为θ
A.保持S闭合,将A板向B板靠近,则θ增大
B.保持S闭合;将A板向B板靠近,则θ不变
C.断开S,将A板向B板靠近,则θ增大
D.断开S,将A板向B板靠近,则θ不变
.I’m sorry I can’t go to the film with you because I have a lot of things to _________.
A.take to
B.get to
C.see to
D.keep to