What is the time when the two hands of a clock coincide between $B.00$ $:$ and $9003$ $8.42\dfrac {8} {11}$ $8.43\dfrac {7} {11}$ $8.44\dfrac {8} {11}$ $8:43$

$Q.7A$ $:$ In how many ways can $10$ true or false questions be answered incorrectly? $7B,$ How many times in a day do the hands of a clock coincide. A $1024$ ways, $S$ $11$ times $B$ B $1023$ ways, 22 times $C$ $1025$ ways, $S$ $23$ times $mθs$ $0$ None of these

$51.$ Two $0$ hands (hour and minute) of $a$ clock coincide at $120^{2}c$ o'clock. $β$ After how much time will they coincide again?