The correct statements among (a) to (d) regarding H₂ as a fuel are :
(a) It produces less pollutants than petrol.
(b) A cylinder of compressed dihydrogen weighs 30 times more than a petrol tank producing the same amount of energy.
(c) Dihydrogen is stored in tanks of metal alloys like NaNi₅.
(d) On combustion, values of energy released per gram of liquid dihydrogen and LPG are 50 and 142 KJ, respectively.