\(\log_{2} y^{\frac{1}{2}} = \log_{5} 125\)

\(\log_{2} y^{\frac{1}{2}} = \log_{5} 5^{3} = 3\log_{5} 5 = 3\)

\(\log_{2} y^{\frac{1}{2}} = 3 \implies y^{\frac{1}{2}} = 2^{3} = 8\)

\(y = 8^{2} = 64\)