1/ How many times a minute does a boat bob up and down on ocean waves that have a wavelength of 38.0 m and a propagation speed of 4.75 m/s?

2/Twin jet engines on an airplane are producing an average sound frequency of 4030 Hz with a beat frequency of 2.800 Hz. What are their individual frequencies (in Hz)? (Enter your answer to the nearest 0.1 Hz.) Hz (smaller) Hz (larger)

3/Storms in the South Pacific can create waves that travel all the way to the California coast, which is 12,000 km away. How long does it take them if they travel at 17.7 m/s? days

4/What is the wavelength (in m) of an earthquake that shakes you with a frequency of 11.5 Hz and gets to another city 81.0 km away in 12.0 s?