`S_1` and `S_2` are two hollow concentric spheres enclosing charges `Q` and `2Q`, respectively, as shown in figure.
i. What is the ratio of the electric flux through `S_1` and `S_2`?
ii. How will the electric flux through sphere `S_1` change if a medium of dielectric constant 5 is introduced in the space inside `S_1` in place of air.
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