A horizontal insulated cylinder of volume V is divided into four identical compartments by stationary semi-permeable thin partitions as shown. The four compartments from left are initially filled with 28 g helium, 160 g oxygen, 28 g nitrogen and 20 g hydrogen respectively. The left partition lets through hydrogen, nitrogen and helium while the right partition lets through hydrogen only. The middle partition lets through hydrogen and nitrogen both. The temperature T inside the entire cylinder is maintained constant. After the system is set in equilibrium,
(a) pressure of helium is 14 RT/V
(b) pressure of oxygen is 20RT/ V
(c) pressure of nitrogen is 4RT/3V
(d) pressure of hydrogen is 10RT/V