Consider an "Event X," which is observed in reference frame P with spacetime coordinates (x, t) = (1500 m, 3.5 μs). Calculate the spacetime coordinates (i) of Event X in reference frame P' as it moves at a velocity of 0.90c along the positive x-axis and (ii) in reference frame P'' as it moves at a velocity of 0.90c along the negative x-axis.