09.35: A piece of an ideal fluid is marked a
t dw 4r6yg--tys it moves along a horizontal streamline through a pipe, as shown in the figure. In Region I, the speed of the fluid on the streamli
dyy-wgt t -4r6ne is V. The cylindrical, horizontal pipe narrows so that the radius of the pipe in Region II is half of what it was in Region I. What is the speed of the marked fluid when it is in Region II?