In a given arrangement (a) find out velocity of water coming out of C
(b). Find out pressure A, B and C

Explanation

(a). Applying Bernoulli's equation between liquid surface and point 'C'
`p_(a)+(1)/(2)rhov_(1)^(2)=p_(a)-rhogh_(3)+(1)/(2)rhov_(2)^(2)`
through continuity equation `Av_(1)=av_(2),v_(1)=(av_(2))/(A)`
`implies(1)/(2)rho(a^(2))/(A^(2))v_(2)^(2)=-rhogh_(3)+(1)/(2)rhov_(2)^(2)`
`v_(2)^(2)=(2gh_(3))/(1-(a^(2))/(A^(2))),V_(2)=sqrt((2gh)/(1-(a^(2))/(A^(2))))`
(b). Pressure at A just outside the tube `p_(A)=p_(atm)+rhogh_(1)`
for pressure at B: `p_(A)+0+0=p_(B)+rhogh_(2)+(1)/(2)rhov_(B)^(2)`
`p_(B)=P_(A)-rhogh_(2)-(1)/(2)rho((2gh_(3))/(1-(a^(2))/(A^(2))))`
Pressure at C: `p_(C)=p_(atm)`