= 7.5 + 10.5 = 18km" alt=" < s> = 7.5 + 10.5 = 18km" align="absmiddle" class="latex-formula">
18km = 1800m
= 600 + 900 = 1500c" alt=" < t> = 600 + 900 = 1500c" align="absmiddle" class="latex-formula">
= \frac{1800}{1500} = 1.2 \frac{m}{c} " alt=" < v> = \frac{1800}{1500} = 1.2 \frac{m}{c} " align="absmiddle" class="latex-formula">