maybe there is an oceanographer out there that can help me out with this:

"an underwater earthquake in the ocean generates a tsunami with a wavelength of 200 km and a height of 1.5. it travels in water that is uniformly deep (3km) until it reaches an inlet, which is 4m deep. when it is in the inlet, what will be its:
a. speed (c)
b. period (t)
c. wavelength (L)
d. height (h)"

Tsunamis act as shallow water waves, so the equation for speed (c) is the square root of gravity (9.8 m/s) * depth which I figured to be 171 m/s in the ocean and 6.26 m/s in the inlet.

I know c=L/t for deep water waves but deep water waves have a different formula for speed = (g/2*pie) * t or 1.56 m/s * t. but I don't know the c=L/t relationship for short water waves so I am unable to figure out period, wavelength and height for this problem. any help would be appreciated