Aspacecraft is traveling with a velocity of v0x = 6580 m/s along the +x direction. two engines are turned on for a time of 907 s. one engine gives the spacecraft an acceleration in the +x direction of ax = 1.81 m/s2, while the other gives it an acceleration in the +y direction of ay = 8.05 m/s2. at the end of the firing, what is a) vx and b) vy?