问题
X线平均波长与最短波长的关系是
A:λmean=3λmin
B:λmean=2.5λmin
C:λmean=2λmin
D:λmean=1.5λminE.λmean=λmin
B:λmean=2.5λmin
C:λmean=2λmin
D:λmean=1.5λminE.λmean=λmin
正确答案是：
