A:∅
B:R
C:(1,2)
D:(﹣∞,1)∪(2,+∞)
— How do you like the regulations of our school?
— The regulations are strict with the students and they require that students _______ at least 90% of the lectures.
读我国沿“北纬30°地形剖面图”,回答下列问题.
设a∈{-1,0,1,2,3},则使函数y=xa的定义域为R且为奇函数的所有a的值有( )