Given below are two statements :

Statement I : PN junction diodes can be used to function as transistor, simply by connecting two diodes, back to back, which acts as the base terminal.

Statement II : In the study of transistor, the amplification factor $$\beta$$ indicates ratio of the collector current to the base current.

In the light of the above statements, choose the correct answer from the options given below.

Zener breakdown occurs in a p $$-$$ n junction having p and n both :

If an emitter current is changed by 4 mA, the collector current changes by 3.5 mA. The value of $$\beta$$ will be :

Identify the correct output signal Y in the given combination of gates (as shown) for the given inputs A and B.