Respuesta :

ANSWER

[tex]8km/hr[/tex]

EXPLANATION

The average speed

[tex] = \frac{distance}{time} [/tex]

Distance=4km

Time=30mins

Convert time to hours.

Time =0.5hrs

The average speed

[tex] = \frac{4}{0.5} [/tex]

[tex] = 8km/hr[/tex]