假设模拟信号的最高频率为6MHz,采样频率必须大于()时,才能使得到的样本信号不失真。
A.6MHz
B.12MHz
C.18MHz
D.20MHz
参考答案:B
. It was an agreement ________ could not be changed.
A.of which details
B.whose the details
C.the details of which
D.all whose details
用何种方法可以诊断疼痛的虚实()。
A.痛时姿势
B.疼痛的部位
C.痛处喜按或拒按
D.痛处的颜色
E.痛处皮肤温度