A particle is constrained to move in one dimension according to the relation \(x=3t^{3}\)[x equals 3 t cubed], where \(x\) is the position from the origin in meters and \(t\) is time in seconds. What is the acceleration in meters per second squared of the particle at \(t=7\) seconds?

W) 18 X) 126 Y) 441 Z) 1029
X) 126