2.
s = 280km
t = 4h
V = ?
[tex]v = \frac{s}{t} = \frac{280km}{4h} = 70 \frac{km}{h} [/tex]
3.
V = 6km/h
s = 1500m = 1,5km
t = ?
[tex]v = \frac{s}{t} | \times t \\ s = v \times t | \div v \\ t = \frac{s}{v} [/tex]
[tex]t = \frac{1.5km}{6 \frac{km}{h} } = \frac{15}{60} = \frac{1}{4} h = 15min[/tex]
