Problem 6.233

(a) What isotope is produced from the alpha-radioactive \(\mathrm{Ra}^{226}\) as a result of five alpha-d isintegrations and four \(\beta\) - -disintegrations? (b) How many alpha- and \(\beta\) -decays does \(U^{238}\) experience before turning finally into the stable \(\mathrm{Pb}^{206}\) isotope?