A square wire loop with $1\mathrm{.}9$ m sides is perpendicular to a uniform magnetic field, with half the area of the loop in the field as shown in the figure. The loop contains an ideal battery with emf $\backslash (\backslash$mathscr$\{\backslash$&$\}=24\backslash$mathrm$\{$~V$\}\backslash ).$ If the magnitude of the field varies with time according to $\backslash ($ B $\backslash )\backslash (=0\mathrm{.}035\backslash$mathrm$\{$~T$\}-(0\mathrm{.}81\backslash$mathrm$\{$~T$\}/\backslash$mathrm$\{$s$\})$ t $\backslash ),$ with $\backslash ($ B $\backslash )$ in teslas and $\backslash ($ t $\backslash )$ in seconds, what are

$($a$)$ the net emf in the circuit and

$($b$)$ the direction of the $($net$)$ current around the loop?

$($a$)$ V

$($b$)$