[填空题]
(a) What resonant freqe6vufa tx q(q.iu, 6l5u34 d o6kftis, wt1(kyeency would you expect from blowing across the top of an empty soda bottle that is 18 cm deep, if you assumed it was a closed 1fkk4eti,(6dos 3ytw tube? Hz (b) How would that change if it was one-third full of soda? Hz
