A mixture of `H_(2),He and O_(2)` with mass ratio equal to the ratio of their atomic weight is present in compartment-II of a cylinder as shown in figure. The SPM is fixed by stoppers such that it divides the cylinder into three equal parts. Find the ratio of pressure in the three parts at equilibrium.
[If the answer is a : b: c then fill in OMR sheet as `a + b+c`. For example if `2 : 6 : 8` then `1+3+4 =8`]
