At what temperature will the rms speed of oxygen molecules become just sufficient for escaping from the Earth' atmosphere? (Given : Mass of oxygen molecule (m) = 2.76 × 10–26kg Boltzmann' constant kB = 1.38 × 10–23JK–1) :-
(1) 2.508 × 104K
(2) 8.360 × 104K
(3) 5.016 × 104K
(4) 1.254 × 104K
