[tex]\bold{a)} \ 36 \ km/h=36 \ 000 \ m/3 \ 600 \ s=10 \ m/s; \\ 9 \ m/h=9 \ 000 \ m/3 \ 600 \ s=2,5 \ m/s; \\ 18 \ km/h=18 \ 000 \ m/3 \ 600 \ s=5 \ m/s; \\ 72 \ km/h=72 \ 000 \ m/3 \ 600 \ s=20 \ m/s; \\ 54 \ km/h=54 \ 000 \ m/3 \ 600 \ s=15 \ m/s; \\ 90 \ km/h=90 \ 000 \ m/3 \ 600 \ s=25 \ m/s.[/tex]
[tex]\bold{b)} \ 1,2 \ km/min=1 \ 200 \ m/60 \ s=20 \ m/s; \\ 0,6 \ km/min=600 \ m/60 \ s=10 \ m/s; \\ 0,9 \ km/min=900 \ m/60 \ s =15 \ m/s; \\ 0,15 \ km/h=150 \ m/3 \ 600 \ s=0.0416 m/s.[/tex]
