我国下列省份与俄罗斯接壤的是（）
A、黑龙江
B、内蒙古
C、吉林
D、新疆
参考答案：A, B, C, D
设集合M={-1，0，1}，N={x|x2=x}，则M∩N=[ ]
A.{-1，0，1}
B.{0，1}
C.{1}
D.{0}
---____ do you study for a math test? ---I study math ____ lots of exercises.
A．What, by doing
B．How, by doing
C．How, doing
D．What, doing
