[填空题]
A light plane is headed due ve* u6zps-, ldsous ; 6v8xtnn hp0gp1jx1th with a speed of 155$ \mathrm{~km} / \mathrm{h}$ relative to still air. After 1.00 hour, the pilot notices that they have covered only 125 km and their direction is not south but southeast $\left(45.0^{\circ}\right) $. What is the wind velocity? $v_{wind}$ = km/h $\text { The direction of the wind is } \theta$= $^{\circ} $ north of east