Determine the torque which must be applied to link $2$ given that $l_1=9\mathrm{.}0,l_2=2\mathrm{.}0,l_3=13\mathrm{.}0,l_4=7\mathrm{.}0($in cm$).$ Additionally, $m_3=0\mathrm{.}5kg,I_{G_3}=2\mathrm{.}52{10}^{-3}kg-m^2,m_4=0\mathrm{.}8kg,I_{G_4}=8\mathrm{.}00{10}^{-4}kg-m^2.$