An airplane is flying horizontally at constant velocity of \( 60 \, \text{m/s} \) at a height \( 540 \, \text{m} \). A box is released from the airplane. If the velocity (in m/s) with which the box lands on the ground is \( 20X \), then \( X \) is ________. (\( g = 10 \, \text{m/s}^2 \))
