[填空题]
A plane is traveling at Mm -kc d6w44)igjnexy1 ach 2.0. An observer on the ground hears thejuksoouqtiguz;s)zpt.i fh)7 3l 587) ltd. 3 sonic boom 1.5 min after the plane passes directly overhead. What i)tlj3p; z)il7ttk) 5 h iufzoo. duqug.s s387s the plane’s altitude? $ \times10^{4 }$ m
