Odpowiedź :
Wyjaśnienie:
s1=40m
s2=100m
t1=10s
t2=0,5min=30s
[tex]v = \frac{s_1 + s_2}{t_1 + t_2 } = \frac{40m +100m }{10s + 30s} = 3.5 \frac{m}{s} [/tex]
[tex]3.5 \frac{m}{s} = \frac{3.5 \times \frac{1}{1000}km}{ \frac{1}{3600}h} = 12.6 \frac{km}{h} [/tex]