Decode the following instructions and check whether the following statements gets executed. If so$,$ trace the output for the values of $a,b$ and c

where all are character variables:

$a={?}^{\text{'}}{B}^{\text{'}}$

$b={?}^{\text{'}}{b}^{\text{'}}$

$a=a$&$b$

$b=a|b$

$c={?}^{\text{'}}{c}^{\text{'}}$&$b$