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For Radium 3Ra, (i) Replace X and Y in the following reactions with the missing particles and /or nuclei: 3Ra > 3%3Fr + X and 3Ra > 23%an + Y and identify each decay. [Note that X and Y may each denote more than one particle] (ii) Given that the halflife for the 3Ra decay into %3Fr is 151/2 = 2.75 min, What mass of 3Ra would be left after 2 hours if the initial mass was 1 pg