设A、B均为n阶矩阵,则下列各式中正确的是( )。
A.A2-E=(A+(A-
B.(A+(A-=A2-B2
C.(A2=A2B2
D.(A+2=A2+2AB+B2
参考答案:A
--- I once got lost during my first visit to Beijing.
-- Oh, did you? You _______ me as your guide.
A.might have asked
B.could ask
C.would have asked
D.would ask
根据《危险废物污染防治技术政策》有关规定,( )属于《危险废物污染防治技术政策》中的特殊危险废物。
A.医院临床废物
B.多氯联苯类废物
C.生活垃圾焚烧飞灰
D.废矿物油
E.废乳化液