In Geiger Marsden alpha scattering experiments , a beam of alpha particles emitted from $Bi_{83}^{214}$ were directed to strike a gold foil and various observations were made. Now answer the following questions. The penetration power of $ \alpha , \beta \text{ and } \gamma $ are related as:

$\alpha > \beta > \gamma$ $\gamma > \beta > \alpha$ $\beta > \gamma >\alpha$ $\beta > \alpha > \gamma$

$\gamma > \beta > \alpha$

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