In 1960, the U. S. Navys bathyscaphe Trieste (a submersible) descended to a depth of 10 912

Question:

In 1960, the U. S. Navy’s bathyscaphe Trieste (a submersible) descended to a depth of 10 912 m (about 35 000 ft) into the Mariana Trench in the Pacific Ocean.
(a) What was the pressure at that depth? (Assume that seawater is incompressible.)
(b) What was the force on a circular observation window with a diameter of 15 cm?