Respuesta :

Answer:

72 km/h

Step-by-step explanation:

We need to convert units

so:

20 m    -----  1 km -------- 3600 s

1 s         -----  1000 m ----1 h

and solve ot

20 x 1 x 3600 s = 72000  we multiply  numerators

1s x 1000 m x 1 h = 1000  we multiply denominators

we divide de results 72000/1000 = 72