Which of the following statements is true? A: Op-amps are high-gain dc amplifiers B: Op-amps have extremely high input impedance. C: Op-amps have extremely low output impedance. D: All of the above

Sales promotions in markets of high brand similarity can produce a high sales response in the short run but little permanent gain in brand preference over the longer term。（ ）

​In high frequency range, drop in gain is caused by ( )‏ A: bypass capacitors B: coupling capacitors C: transistor's parasitic capacitors D: bias resistors

In high frequency range, drop in gain is caused by ( ) A: bypass capacitors B: coupling capacitors C: transistor's parasitic capacitors D: bias resistors

The<br/>common-base amplifier has _()()()__. A: voltage gain, current gain, and power gain B: voltage gain and power gain, but no current gain C: current gain and power gain, but no voltage gain D: current gain and voltage gain, but no power gain

Americans do not expect to gain and lose friendships naturally as their life changes. For example, they may have a group of close friends in high school that they will remain very close to for the rest of their lives.

The common mode rejection ratio (CMRR) is the ratio of _______. A: the difference mode gain to the common mode gain B: the common mode gain to the difference mode gain C: noninverting gain to inverting gain D: inverting gain to noninverting gain

3. The common mode rejection ratio (CMRR) is the ratio of ________. A) the difference mode gain to the common mode gain B) the common mode gain to the difference mode gain C) noninverting gain to inverting gain D) inverting gain to noninverting gain A: This is the right answer. B: wrong. C: wrong. D: wrong.

The leading group of three continue to the rest of the runners and were soon half a mile clear of them. A: gain ove B: gain around C: gain on D: gain in

得人心者得天下 Those who gain _____ among the people will gain the power.