[填空题]
The lifetimes listed in Tablef xaj 6+g8o1bkrp 39uf9 ow*u1d7p xoa 32-2 are w/l dbs5b y3v,in terms of proper time, measured in a reference frame where the particle is at rest. If a tau lepto/3wb ybslvd ,5n is created with a kinetic energy of 450 MeV, how long would its track be as measured in the lab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $ $ \times 10^{-5}\ \text{m}$
