Periodic waves spread out of the surface of a lake where two women, Jenny and Melissa, are fishing in separate boats 38 meters apart. Each woman's boat bobs up and down 19/min. At a time when Jenny's boat is at a crest, Melissa's boat is at its lowest point, and there are 6 additional crests between them. Calculate the wavelength of these water waves.
And what is the speed of these water waves?