On a spacecraft, two engines are turned on for 789 s at a moment when the velocity of the craft has x and y components of v0x = 5410 m/s and v0y = 8100 m/s. while the engines are firing, the craft undergoes a displacement that has components of x = 2.78 x 106 m and y = 4.73 x 10^6m. find the (a) x and (b) y components of the craft's acceleration.