The avalanche breakdown in $P-N$ junction is due to-

Consider the following statements 1 and 2 and identify the correct answer.

[1] A zener diode is always connected in reverse bias.

[2] The potential barrier of a $\mathrm{P}-\mathrm{N}$junction lies between $0.1 \mathrm{to} 0.3 \mathrm{V}$ approximately.

Two junction diodes one of germanium $\left(\mathrm{Ge}\right)$ and other of silicon $\left(\mathrm{Si}\right)$ are connected as shown in figure to a battery of emf $12 \mathrm{V}$ and a load resistance $10 \mathrm{k\Omega }$. The germanium diode conducts at $0.3 \mathrm{V}$ and silicon diode at $0.7 \mathrm{V}$. When a current flows in the circuit, the potential of terminal $Y$ will be