Pipe A$,$ which is $2\mathrm{.}40$ m long and open at both ends, oscillates at its third lowest harmonic frequency. It is filled with air for which the speed of sound is $343$ m$/$s$.$ Pipe B$,$ which is closed at one end, oscillates at its second lowest harmonic frequency. This frequency of B happens to match the frequency of A$.$ An x axis extends along the interior of B$,$ with x $=0$ at the closed end. $($a$)$ How many nodes are along that axis? What are the $($b$)$ smallest and $($c$)$ second smallest value of x locating those nodes? $($d$)$ What is the fundamental frequency of B$?$