$17-92($a$)$ Find the length of an organ pipe closed at one end that produces a fundamental frequency of $256$ Hz when air temperature is $18\mathrm{.}0$C $.$

L $=[$ Select $]["0\mathrm{.}7777$ m$","0\mathrm{.}5557$ m$","0\mathrm{.}6667$ m$","0\mathrm{.}3337$ m$","0\mathrm{.}2227$ m$","0\mathrm{.}1117$ m$","0\mathrm{.}4447$ m$"]$

$($b$)$ What is its fundamental frequency at $25\mathrm{.}0$C $?$