For the transistor $M_{1}$ in the circuit shown in the figure, $\mu_{n} C_{\text{ox}} = 100\:\mu A/V^{2}$ and $(W/L)=10$, where $\mu_{n}$ is the mobility of electron, $C_{\text{ox}}$ is the oxide capacitance per unit area , $W$ is the width and $L$ is the length.
The channel length modulation coefficient is ignored. If the gate-to-source voltage $V_{\text{GS}}$ is $1\:V$ to keep the transistor at the edge of saturation, then the threshold voltage of the transistor (rounded off to one decimal place) is __________________ $V$.