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i) Speed of sound = $\frac{2d}{t}$ = $\frac{2\times 400}{2.5}$ = 320m/s
ii) Distance = speed x time
$\rightarrow$ 2(x - 400) = 320 x 4.5
x = 1120m
johnmulu answered the question on February 11, 2017 at 08:48
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