滴丸的非水溶性基质是（）
A.PEG6000
B.水
C.液体石蜡
D.硬脂酸
E.石油醚
参考答案：D
Mother often tells Tom ______ too much time playing video games. [ ]
A. not to spend
B. to not spend
C. don't spend
D. doesn't spend
自动、共电电话机用在线路环阻大于500Ω时，取机后测其直流电阻应≤（）Ω。
A.100
B.200
C.300
D.500
