A robot maneuvers itself by using a laser guidance system where the positions of reflective targets, such as at points B and C, are known. By scanning the room with a laser that emanates from point A and sensing the reflections from targets B and C, the robot may compute the direction cosines of position vectors as given below. The locations of other points, such as point D at the base of the ramp, are also known, but such locations do not have reflective targets. Determine the position vector from point A to point D so that the robot may move from its current position to the base of the ramp at point D. Take the coordinates of point B as (0, 0, 122) cm and point C as (250, -45, 90) cm.