A Trough Is Filled with a Liquid of Density $855 \mathrm {~kg} / \mathrm { m } ^ { 3 }$

Multiple Choice

A trough is filled with a liquid of density $855 \mathrm {~kg} / \mathrm { m } ^ { 3 }$ . The ends of the trough are equilateral triangles with sides $7 \mathrm {~m}$ long and vertex at the bottom. Find the hydrostatic force on one end of the trough.

A) $2.5 \times 10 ^ { 5 } \mathrm {~N}$
B) $5.5 \times 10 ^ { 5 } \mathrm {~N}$
C) $4.5 \times 10 ^ { 5 } \mathrm {~N}$
D) $6.5 \times 10 ^ { 5 } \mathrm {~N}$
E) $3.5 \times 10 ^ { 5 } \mathrm {~N}$