[tex]\qquad\qquad\huge\underline{{\sf Answer}}[/tex]
Wavelength, Wavespeed and frequency depends on each other in the following way :
[tex]\qquad \sf \dashrightarrow \: frequency = \dfrac{wave \: \: velocity}{wavelength} [/tex]
[tex]\qquad \sf \dashrightarrow \: f = \dfrac{389}{8} [/tex]
[tex]\qquad \sf \dashrightarrow \: f \approx 48.62 \: \: hertz[/tex]
And we know the Reciprocal relationship between frequency and period ~
So, let's find it's period •
[tex] \sf{\qquad \sf \dashrightarrow \: t = \dfrac{8}{389}} [/tex]
[tex] \sf{\qquad \sf \dashrightarrow \: t \approx 0.02 sec } [/tex]