Answer:
[tex]80\frac{m}{s}[/tex]
Step-by-step explanation:
we know that
[tex]Wave\ speed = (frequency) * (wavelength)[/tex]
Inn this problem we have
[tex]frequency=200\ Hz[/tex]
[tex]wavelength=0.40\ m[/tex]
substitute the values
[tex]Wave\ speed = 200*0.40=80\frac{m}{s}[/tex]