Odpowiedź :
[tex]Dane:\\v = 72\frac{km}{h} = 72\cdot\frac{1000 \ m}{3600\ s} = 20\frac{m}{s}\\t = 15 \ min = 15\cdot60 \ s = 900 \ s\\Szukane:\\s = ?\\\\Rozwiazanie\\\\s = v\cdot t\\\\s = 20\frac{m}{s}\cdot 900 \ s\\\\\boxed{s = 18 \ 000 \ m = 18 \ km}[/tex]