The answer is 11.83.

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Find the difference in gravitational potential energy and equate it to the kinetic energy (translation + rotation):

$\large{U_i - U_f = MgR - \frac{M}{4} g \frac{R}{2} = \frac{7}{8} MgR \\ \frac{7}{8} MgR = \frac{1}{2} \frac{M}{4} v^2 + \frac{1}{2} \frac{(M/4) (R/2)^2}{2} \Big(\frac{v}{(R/2)}\Big)^2 \\ \frac{7}{8} (10)(3) = v^2 \Big(\frac{1}{8} + \frac{1}{16}\Big) \\ v \approx \boxed{11.83}}$