Question

unlike gases water exerts no pressure if there's a structural problem on a submarine the submarine is not likely to be crushed as it descends

Answer 1

Wrong wrong wrong. 
Also false and untrue.

The force of the water against the hull of a submerged submarine is enormous.  The effect of a structural failure can be the immediate
crushing of the entire craft like a beer can.

Answer 2

False Money true it is false