An engine whose sparkplugs fire 120 times a second generates noise at \(120 \mathrm{~Hz}\). The sound level can be reduced by fitting the engine with an exhaust resonator that cancels this primary "note." The resonator is an open-closed tube, with the open end connected to the exhaust system. Sound enters the tube, reflects from the closed end, and re-enters the exhaust system exactly out of phase with the incoming sound. How long must the tube be? Assume a sound speed of \(360 \mathrm{~m} / \mathrm{s}\) in the warm exhaust gases.