椰子汁
参考答案:21(2009.8011)
After dinner they talked about the persons and things _______ they still remembered.
A.which
B.that
C.who
D.what
横向分辨力为()。
A.区分平行于超声束的两个物体的能力
B.区分垂直于超声束的两个物体的能力
C.与深度分辨力相同,取决于声束直径
D.与厚度分辨力相同
E.B和C