Answer:
A) 3.11 Hrs
Explanation:
Wave speed is given by the formula
[tex]Speed = \frac{wavelength}{Time\: period}[/tex]
now we will have
[tex]speed = \frac{40}{0.80}[/tex]
[tex]v = 50 m/s[/tex]
now the time taken by the wave to move the distance 560 km is given as
[tex]t = \frac{distance}{speed}[/tex]
[tex]t = \frac{560\times 10^3}{50}[/tex]
[tex]t = 11200 s[/tex]
t = 3.11 hours