Respuesta :
Answer:
The change in speed is 3m/s
Explanation:
The change is speed is defined as the difference between final and initial speed:
ΔV=[tex]V_{2}-V_{1}[/tex]
where V2 and V1 are the final and initial speeds, respectively.
Plugging in the values
ΔV=7m/s-4m/s=3m/s