Răspuns:
[tex]vm = \frac{d}{t} \: \: \\ v = 4 \frac{m}{s} \: \: t = 5 s\: \: \\ d = v \times t = 20m \: \: \: \\ v = 6 \frac{m}{s} \: \: d = 18 m\: \: \\ t = \frac{d}{v} = 3s \: \: \: \\ d = 4m \: \: \: \: t = \frac{1}{2} s \\ v = 4 \times 2 = 8 \frac{m}{s} [/tex]
