If a rubber ball falls from a height \( h \) and rebounds upto the height of \( \frac{h}{2} \). The percentage loss of total energy of the initial system as well as velocity ball before it strikes the ground, respectively, are:
\( 50\% \), \( \sqrt{\frac{gh}{2}} \)
\( 40\% \), \( \sqrt{2gh} \)
\( 50\% \), \( \sqrt{gh} \)
\( 50\% \), \( \sqrt{2gh} \)