The figure shows a rectangular wire loop. The magnetic field is given by $3\mathrm{.}00$y$^2$t$^4,$ with B in teslas, y in meters, and t in seconds. The coordinates are x$1=0\mathrm{.}300$ m$,$ x$2=0\mathrm{.}600$ m$,$ y$1=0\mathrm{.}500$ m$,$ and y$2=0\mathrm{.}700$ m$.$

a$)$ What is the induced emf $($V$)$ at time t $=4\mathrm{.}00$ s$?$

b$)$ What is the direction of the induced emf?