Resposta :
20min=1200s
v=d/t
v=1200/1200
v=1m/s
1.3,6=3,6km/h
Espero ajudar❤
[tex]\large\boxed{\begin{array}{l} \sf{1\,km\rightarrow1000\,m}\\\sf{x\rightarrow1200\,m}\\\sf{x=\dfrac{1\,km\cdot1200\,m}{1000\,m}}\\\sf x=1,2\,km\end{array}}[/tex]
[tex]\large\boxed{\begin{array}{l} \sf 1\,h\rightarrow60\,min\\\sf x\rightarrow20\,min\\\sf x=\dfrac{1\,h\cdot20\,min}{60\,min}\\\sf x=\dfrac{1}{3}h\end{array}}[/tex]
[tex]\large\boxed{\begin{array}{l} \sf V_m=\dfrac{\Delta S}{\Delta t}\begin{cases}\sf V_m=?\,km/h\leftarrow velocidade\, m\acute{e}dia\,escalar\\\sf \Delta S=1,2\,km\leftarrow variac_{\!\!,}\tilde{a}o\,de\, espac_{\!\!,}o\\\sf \Delta t=\dfrac{1}{3}h\leftarrow variac_{\!\!,}\tilde{a}o\,de\,tempo\end{cases}\\\sf V_m=\dfrac{1,2\,km}{\dfrac{1}{3}h}=1,2\cdot\dfrac{3}{1}=3,6\,km/h\end{array}}[/tex]