8. Find the width of the river

A person in the helicopter flying at the height of 670 $m$ above the river, observes two objects lying opposite to each other on either bank of a river. The angles of depression of the objects are 45$^{\circ}$ and 30$^{\circ}$. Then, the width of the river is 1829.441831.441830.441828.44 $m$.

 

(Note: Substitute $\sqrt{3} = 1.732$ if necessary.)