P$11\mathrm{.}25$ At what speed, when pumping water, should the $105$ cm pump of Fig. $11\mathrm{.}7$ b be run to realize $($a$)$ a head of $30\mathrm{.}48$ m $?$ For this condition, what are the resulting $($b$)$ flow rate and $(\backslash ($ c $\backslash ))$ brake horsepower?

$($a$)$

$($b$)$