[填空题]
A uniform narrow tube 1.vy i82v9)gfwidz bg+s54d*q f*+a efn80 m long is op/f t- zz r:oagcj+jr.9en at both ends. It resonates at two successive harmonics of frequencies 275 Hz and 330 Hz. Wh j f-:cgrztzo/ ra+9.jat is
(a) the fundamental frequency, Hz
(b) the speed of sound in the gas in the tube?$\approx$ $ \times10^{2 }$ m/s