1. A hollow cubical box is .30 m. This box is floating in a lake 1/3 of its height beneath the surface. The walls of the box have neglibe thickness. Water is poured into box. what is the depth of the water in the box at the instant the box begins to sink? pwater= 1000kg/m3 Fb= Pfluid G V D=M/V okay so i got the volume of the whole of the box to be .027 m(3) then the volume of the submurged by multyplying .1m * .3m * .3m = .009m I figure i need to know the buoyent force that is pushing up on the cube before the water is added. so i did 1000kg/m(3) (9.8m/s)(.009m) so once i get that force what i would it set it equal to!! help!