Uu接口中，下列哪些属于层二部分？（）
A.MAC
B.RLC
C.RRC
D.PDCP
参考答案：A, B, C, D
To her disappointment, what she had devoted herself to in nothing but failure.
A．resulting
B．results
C．has resulted
D．resulted
液体动压润滑的工作原理是什么？
