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(i) To allow all radiations to penetrate
(ii) On entering the tube, the radiation ionizes argon gas. The positive ions flows towards the cathode and negative ions towards the anode. This creates potential difference that results to flow of pulse current.
(iii) To absorb the energy of positive ions before they cause secondary electron emission.
johnmulu answered the question on June 6, 2017 at 08:22
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