I thought I had this problem on lock, but apparently I was wrong in my methods. My original answer was 7.97i + 3.92j but that is incorrect. I've tried other methods but now I'm just lost. I need some assistance or I'm a dead man. "A particle is in uniform circular motion about the origin of an xy coordinate system, moving counterclockwise with a period of 8.00 s. At one instant, its position vector (from the origin) is r = (6.00 m) i - (5.00 m) j. At that instant, what is its velocity in unit-vector notation?"