【简答题】She broke into(teal')__________when she heard the news that her son was badly injured.
【判断题】两个数的差是15.8,如果被减数减少3,减数增加3,它们的差不变. [ ]
【单选题】按某种标志将所有总体单位分类,然后在各类中按简单随机抽样方式抽取样本单位的方式,叫 ()
【单选题】Lucy looks ________when she performs. [ ]
【单选题】理想变压器的电压变比关系描述正确的是:
A.
输入电压和输出电压之比,等于原副线圈的比值,两者同相位
B.
输入电压和输出电压之比,等于原副线圈的比值,两者位相差为 π/2
C.
输入电压和输出电压之比,等于原副线圈的比值,两者位相差为- π/2
D.
输入电压和输出电压之比,等于原副线圈的比值,两者位相差为 π
【单选题】She said to her son, “Don’t play in the street.”
A.
She said to her son that he didn’t play in the street.
B.
She told to her son not to play in the street.
C.
She told her son that he didn’t play ion the street.
D.
She told her son not to play in the street.
【单选题】She performs the songs with______.