t = t2 - t1 = d/v2 - d/v1
9 X' W( } Q4 N, }" v% v- H; mtvb now,tvbnow,bttvb5.39.217.771 v, }9 |; G0 @/ J
so answer is :5.39.217.776 J8 B/ w- {- C$ K p4 A! y: k0 [
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d = t * v1 * v2 / (v1-v2) |