A single-phase $SCR$ based $ac$ regulator is feeding power to a load consisting of $5 \Omega$ resistance and $16 \: mH$ inductance. The input supply is $230 \: V$, $50 \: Hz$ ac. The maximum firing angle at which the voltage across the device becomes zero all throughout and the rms value of current through $SCR$, under this operating condition, are
- $30^ \circ$ and $46 \: A$
- $30^\circ$ and $23 \: A$
- $45^\circ$ and $23 \: A$
- $45^\circ$ and $32 \: A$