A chirped Gaussian pulse with the positive chirp parameter K=1 travels through a single- mode optical fibre. The central wavelength of the pulse is ho=1550 nm, which corresponds to the value of the group velocity dispersion parameter of the fibre B,=-20 ps'/km. The temporal pulse width is T,=10 ps. After traveling some distance z through optical fiber the pulse became transform-limited. What is the value of the distance?