# Three materials X, Y and Z having relative permittivity 2.5, 3.0 and 4.0 respectively are used in a single core

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Three materials X, Y and Z having relative permittivity 2.5, 3.0 and 4.0 respectively are used in a single core cable. The materials on inner most and outer most layer respectively should be (a) X and Y (b) Y and Z (c) X and Z (d) Z and X

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