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