Cuttlefish use jet propulsion to move rapidly. To do this, a cuttlefish fills its muscular mantle cavity with water and then quickly expels the water through a tube$-$like opening. The mass of a cuttlefish is about the same as the mass of water of the same volume. A $15-$cm$-$long and $5\mathrm{.}0-$cm$-$wide cuttlefish, initially at rest, is moving at a speed of $4\mathrm{.}0$ m$/$s after expelling the water from its body. Assume that the cuttlefish has a cylindrical form, the mantle cavity has a form of a cylinder with length of $9\mathrm{.}0$ cm$,$ and the thickness of the muscle surrounding the sides of the cavity is $1\mathrm{.}0$ cm$.$ Estimate the speed of the expelled water relative to the sea bed?