A gate valve is being used as a shut$-$off valve in a pipe system. When the valve is fully open, the flow through the $8-$cm diameter pipe is $50$ L$/$minL$/$min $.$ What is the head loss at the gate valve? One liter is $0\mathrm{.}001$ cubic meters. The flow of water in a pipe passes through a sudden expansion from d$1$d$1=8$ cmcm to d$2$d$2=10$ cmcm $.$ If the flow rate is QQ $=0\mathrm{.}05$ m$3/$sm$3/$s $,$ what is the pressure drop due to expansion? The specific weight of water is ww $=9\mathrm{.}802$ kN$/$m$3$