E.M. waves with frequencies greater than critical frequency of ionospherecan not because for communication because

E.M. waves with frequencies greater than critical frequency of ionosph

1.	E.M. waves with frequencies greater than critical frequency of ionospherecan not because for communication because
Answer» R.I of ionosphere becomes very HIGH for `fgtf_(C)` R.I of ionosphere becomes very low for `fgtf_(c)` R.I of ionosphere becomes very high for `f lt f_(c)` None ANSWER :A

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E.M. waves with frequencies greater than critical frequency of ionospherecan not because for communication because

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