理想运放工作在线性区时输入端有两个主要的特点，分别为__________和_____________ 。

A.Thepriceoftheproduct.
B.Thechargeoftheservice.
C.Thedeliveryofhisorder.
D.Thepackingofthegoods.

A.Giving a lecture.
B.Taking an interview.
C.Preparing a party.
D.Having an exam.

A.Its food is delicious.
B.Its price is reasonable.
C.It is close to his office.
D.It provides good service.

A.By sea.
B.By air.
C.By train.
D.By truck.