人体MRI最常用的成像原子核
A.氢原子核
B.钠原子核
C.钙原子核
D.磷原子核
E.氮原子核
参考答案:A
Your understanding on the theory is____ satisfactory. You must read more after class.
A.far from
B.up to
C.along with
D.free of
目前高速公路监控分为收费监控和()两类。