b$)($i$)$ Sketch three$-$cyele waveforms of $c_a{I}_L$ and $V_L$ if devices $D_1$ and $D_2$ of Figure Q$1$ are replaced with thyristors fired at an angle $=\frac{}{3}$

$($ii$)$ Sleetch three$-$cycle waveforms of of $c_2$ I and $V_6,$ if devices $D_3$ and $D_4$ of Figurel ate replaced with thyristore and fired at an angle $a=5\frac{}{6}.\text{'}3$