已知复数z1=2+i，z2=1-i，则复数z1·z2的虚部是_______________
-1
,故虚部为－1
I don’t like this job. Next year when you visit me, hopefully I ______ in a major IT company.
A．have worked
B．am working
C．work
D．will be working
在鸡蛋的结构图（如图所示）中，将来能发育成雏鸡的结构是图中的（
A．①
B．②
C．③
D．⑤
,故虚部为－1
,故虚部为－1