Respuesta :

Answer:

the speed is 20 m/s

Step-by-step explanation:

The computation of the speed is as follows

As we know that

Speed = Distance ÷ time

where,

Distance is 420 meters

And, the time is 21 seconds

So, the speed is

= 420 ÷ 21

= 20 m/s

hence, the speed is 20 m/s

We simply applied the above formula so that the correct value could come

And, the same is to be considered