Hydrazine, a component of rocket fuel, undergoes combustion to yield  $N_2$ and  $H_{2}O.$
$N_2{H}_4\left(l\right)+O_2\left(g\right)\to N_2\left(g\right)+2H_{2}O\left(l\right)$ 
What is the change in internal energy for above reaction of $N_2{H}_4$ (in kJ/mole)?
Given: Reaction                                                                            $\Delta H\left(kJ\right)$

$2N{H}_3\left(g\right)+3N_{2}O\left(g\right)\to 4N_2\left(g\right)+3H_{2}O\left(l\right)$                      $-1011kJ$

$N_{2}O\left(g\right)+3H_2\left(g\right)\to N_2{H}_4\left(l\right)+H_{2}O\left(l\right)$                              $-317kJ$
$4N{H}_3\left(g\right)+O_2\left(g\right)\to 2N_2{H}_4\left(l\right)+2H_{2}O\left(l\right)$                       $-286kJ$

$H_2\left(g\right)+\frac{1}{2}{O}_2\left(g\right)\to H_{2}O\left(l\right)$                                                  $-285kJ$