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A:Chicken with vegetables and two bowls of rices.
B:Chicken with vegetables and two bowls of rice.
C:Chickens with vegetable and two bowl of rice.
设集合S={A0,A1,A2,A3},在S上定义运算为:Ai⊕Aj=AK其中k为i+j被4除的余数,i、j=0,1,2,3.满足关系式=x⊕xA2=A0的x(x∈S)的个数为( )
下列各项中属于特异性免疫的是( )
△ABC的两个顶点为A(-4,0),B(4,0),△ABC周长为18,则C点轨迹为( )