(-2a2)•(3ab2-5ab3)+8a3b2.
原式=-6a3b2+10a3b3+8a3b2
=2a3b2+10a3b3.
I was _____ a picture with Jenny's camera.[ ]
A. take
B. took
C. taking
办理卡片激活时密码遗忘的,先办理密码挂失,再通过主管授权办理卡片激活、密码重置。