In the combination of the following gates, the output Y can be written in terms of inputs A and B as :- 

1. 

2. 

3. $\overline{\mathrm{A}.\mathrm{B}}+\mathrm{A}.\mathrm{B}$

4. 

In the circuit shown in the figure, the input voltage V_i is 20 V, V_BE = 0, and V_CE = 0. The values of I_B, I_C and $\beta$ are given by:

1.  ${\mathrm{I}}_{\mathrm{B}} = 40 \mathrm{\mu A}, {\mathrm{I}}_{\mathrm{c}} = 10 \mathrm{mA}, \mathrm{\beta } = 250$

2. ${\mathrm{I}}_{\mathrm{B}} = 25 \mathrm{\mu A}, {\mathrm{I}}_{\mathrm{c}} = 5 \mathrm{mA}, \mathrm{\beta } = 200$

3. ${\mathrm{I}}_{\mathrm{B}} = 20 \mathrm{\mu A}, {\mathrm{I}}_{\mathrm{c}} = 5 \mathrm{mA}, \mathrm{\beta } = 250$

4. ${\mathrm{I}}_{\mathrm{B}} = 40 \mathrm{\mu A}, {\mathrm{I}}_{\mathrm{c}} = 5 \mathrm{mA}, \mathrm{\beta } = 125$

In a common-emitter transistor amplifier, the audio signal voltage across the collector is 3V. The resistance of the collector is 3k$\Omega$. If current gain is 100 and the base resistance is 2k$\Omega$, the voltage and power gain of the amplifier is:

1. 15 and 200

2. 150 and 15000

3. 20 and 2000

4. 200 and 1000

The given circuit has two ideal diodes connected as shown in the figure below. The current flowing through the resistance R₁ will be:
     

What is the output Y in the following circuit, when all the three inputs A, B, C are first 0 and then 1? 
                        

1.  0, 1

2.  0, 0

3.  1, 0

4.  1, 1