As ocean waves approach the shore, friction with the ocean bottom causes them to slow down. if the frequency is the same, how will this affect the wavelength of the waves?

If the frequency is the same, the wavelength of the waves would decrease. The wave velocity depends on frequency and wavelength. If the velocity decreases to be the same as the frequency then the wavelength should decrease as well.

Although, I'm not very confident<(＿　＿)>

the precambrian aged rocks could be found in australia. australia is a region that has a lot of ancient civilization history from million years ago. in this region, there are a lot of recognizable fossils buried in its land which is considered a precambrian-aged rocks