A long, rigid conductor, lying along an $x$ axis, carries a current of $7.0 \mathrm{~A}$ in the negative $x$ direction. A magnetic field $\vec{B}$ is present, given by $\vec{B}=3.0 \mathrm{i}+8.0 x^{2} \hat{\mathrm{j}}$, with $x$ in meters and $\vec{B}$ in milliteslas. Find, in unit-vector notation, the force on the $2.0 \mathrm{~m}$ segment of the conductor that lies between $x=1.0 \mathrm{~m}$ and $x=3.0 \mathrm{~m}$.