For the manometer as shown,

$($a$)$ Find the absolute pressure at point A in terms of densities r water and r mercury $,$ lengths h $1,$ h $2,$ and h $3,$

atmospheric pressure Patm $,$ and gravitational acceleration g$.$

$($b$)$ Find the absolute pressure at point A using the result in part $($a$).$

rwater $=1000$ kg$/$m$3,$ r mercury $=13600$ kg$/$m $3,$

h $1=6$ cm$,$ h $2=10$ cm$,$ h $3=5$ cm$,$

Patm $=105$ Pa$,$ g $=9\mathrm{.}8$ m$/$s $2$