若2x3ym与-3xny2是同类项,则m-n=______.
∵2x3ym与-3xny2是同类项,
∴n=3,m=2,
∴m-n=-1.
故答案为:-1.
检测梗死心肌活力用哪种显像方法
A.99mTc-MIBI两日法
B.201Tl/99mTcO显像减影法
C.99mTc-MIBI/18F-FDG双核素法
D.99mTcO显像
E.99mTc-(V)-DMSA
Part 3
Questions 19-25
Ifa company wants to make it possible to make a training specification, it should ______.
A.know successful performance of the job
B.make it clear the best methods to use
C.collect job descriptions and job specifications
D.have proper behavior, knowledge and skills