Answer:
0.4 m/s
Step-by-step explanation:
First of all, let's find the frequency of the wave, which is equal to the reciprocal of its period:
![f=(1)/(T)=(1)/(5 s)=0.2 Hz](https://img.qammunity.org/2020/formulas/physics/middle-school/lj141li8hv52v9rapu6qxzeax6a5v94n4j.png)
Now we can find the wave speed using the formula:
![v=f\lambda](https://img.qammunity.org/2020/formulas/physics/middle-school/my0ag4u726vdxx68ivkjdtgrzdvbfvxulf.png)
where
f = 0.2 Hz is the frequency
is the wavelength
Substituting, we find
![v=(0.2 Hz)(2 m)=0.4 m/s](https://img.qammunity.org/2020/formulas/physics/middle-school/j2ammlvnhb61wlowfbxi5bwa798zzia0ik.png)