What occurs when a rock crushes into into a pile of fragments

If a || b and e || f, what is the value of y ?

Aroom with dimensions 7.00m×8.00m×2.50m is to be filled with pure oxygen at 22.0∘c and 1.00 atm. the molar mass of oxygen is 32.0 g/mol. how many moles noxygen of oxygen are required to fill the room? what is the mass moxygen of this oxygen?

Δu of , in kj/kg, as it isto k, (a)as a of , (b) at , (c) at .