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A person, with his ear to the ground, sem o/ xqidc-j8 xwt7*m7.ytww5es a ()7 x :fwkosa 4ncmm9wwre0,l huge stone strike the concrete pavement. A moment later two sounds are heard from the impact: one travels in the air and the other in the concrete, and they are 1,oermn) 9w7(4k:0 lx mcwwfas.1 s apart. How far away did the impact occur? See Table 12–1.$\approx$ $ \times10^{2 }$m
