1.
[tex]Dane:\\s = 600 \ m = 0,6 \ km=\frac{6}{10} \ h = \frac{3}{5} \ h\\t = \frac{1}{2} \ min = \frac{\frac{1}{2}}{60} \ h = \frac{1}{60} \ h\\Szukane:\\v = ?\\\\v = \frac{s}{t}\\\\v = \frac{\frac{3}{5} \ km}{\frac{1}{20}h}=\frac{3}{5}\cdot20 \ \frac{km}{h}\\\\\boxed{v = 120\frac{km}{h}}[/tex]
2.
[tex]Dane:\\s = 4 \ km\\t = 1 \ min \ i \ 40 \ s=(60+40)s = 100 \ s = \frac{100}{3600} \ h = \frac{1}{36} \ h\\Szukane:\\v = ?\\\\v = \frac{s}{t}\\\\v = \frac{4 \ km}{\frac{1}{36} \ h}=4\cdot36 \ \frac{km}{h}\\\\\boxed{v = 144\frac{km}{h}}[/tex]
