Answer
$2.54\;m$.
Work Step by Step
Given values are
Frequency $f=0.55\; /s$
Speed $v =1.4\;m/s$.
Formula for the wavelength of water waves.
$\lambda=\frac{v}{ f}$
Substitute all values.
$\lambda=\frac{1.4\;m/s}{ 0.55\; /s}$
Simplify.
$\lambda=2.54\;m$.
