3. When small ac input signals are required a. channel 1 on the oscilloscope should be used b. the attenuator should be used c. the potentiometer should be adjusted carefully d. the variable dc supply should be used 4. The circuit blocks used to configure two types of transistor amplifiers a. is the common collector circuit block b. is the biased stabilization circuit block c. are the common base/emmiter and RC coupling/transformer coupling circuit blocks d. is the direct coupling circuit block 5. The potentiometers on some of the circuit blocks are used to a. change the value of the resistor b. adjust the dc voltage supply C. configure the amplifier circuit d. adjust the ac input signal