医用加速器X线适宜的能量()
A.<150KV。
B.180KV-270KV
C.600KV-8MV
D.1MV-22MV
E.15MV-30MV
参考答案:D
An e-mail address consists _______letters and dots and the symbol‘@’.
A.in
B.of
C.for
D.with
正常膝关节透明软骨的厚度约为()
A.4mm
B.2mm
C.2.5mm
D.3mm
E.1mm