EK Physics Fluids page 187 question 99+101

[farmin]

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Q.99 When both ends are sealed shut, the pressure is the greatest at point
A
B
C
D <----the lowest point in the pipe.

----------------
/~~~~~~ ~~/
/ A. /
/. /
/___. ___/
/. /
/. / ___________
/__________. /
/D_
http://postimg.org/image/y8n6omjzp/

Why is it D and not A? Isn't D just at atmospheric pressure? Sure it's lower than A but there's only a little bit of water above point D and rho*g*h right?

Q.101 What is the pressure at point C when the pipe is closed and the fluid is at rest?
A 2000Pa
B 3000Pa
C 2000Pa+1atm
D 3000Pa+1atm

Why is it B and not D? Don't you need to account for Atmospheric pressure?

Ugh took me like an hour to draw the diagram then accidentally deleted it on iPad so no undo then gave up and drew a more basic one then turns out the formatting changed... Please see the link provided for the diagram

 

[Patassa]

Q.99 When both ends are sealed shut, the pressure is the greatest at point
A
B
C
D <----the lowest point in the pipe.

----------------
/~~~~~~ ~~/
/ A. /
/. /
/___. ___/
/. /
/. / ___________
/__________. /
/D_
http://postimg.org/image/y8n6omjzp/

Why is it D and not A? Isn't D just at atmospheric pressure? Sure it's lower than A but there's only a little bit of water above point D and rho*g*h right?

I think you have it backwards, D has the greatest height of fluid on top of it, don't let the configuration throw you off. Everywhere in the system has a higher stack of fluid on top of it than D. Also, if the system is sealed, is atmospheric pressure acting on the fluid?