The speed of skater can be given as,
[tex]v=\frac{d}{t}[/tex]Here, v is the speed, d is the distance travelled and t is the time taken.
Substitute the known values,
[tex]\begin{gathered} v=\frac{1.5\text{ km}}{(78\text{ s)(}\frac{1\text{ h}}{60\text{ min}})(\frac{1\text{ min}}{60\text{ s}})_{}} \\ \approx68\text{ km/h} \end{gathered}[/tex]Thus, the speed of skater is approximately 68 km/h.
