在古代印度的种姓制度中属于统治阶级的是
①首陀罗②刹帝利③婆罗门④吠舍[ ]
A．②③
B．①③④
C．①③
D．①②③
答案：A
The teacher says we shouldn't watch TV. It's bad for our eyes. [ ]
A. much too
B. many too
C. too much
D. too many
一圆形建筑物半径为27.5m，若测量半径的误差为±1cm，则圆面积的中误差为（）。
A.±；1.73m2
B.±；1.77m2
C.±；1.32m2
D.±；3.14m2
