A horizontal pipe of non-uniform cross- section allows water to flow through it with a velocity $1\; ms^{-1}$ when pressure is $50\;kPa$ at a point. If the velocity of flow has to be $2 ms^{-1}$ at some other point the pressure at that point should be

Question

$$\begin {array} {1 1} (a)\;50\;kPa & \quad (b)\;100\;kPa \\ (c)\;48.5\;kPa & \quad (d)\;24.25\;kPa \end {array}$$