一道指数英文数学题求解An orchestra tunes to a frequency of 440,which sounds the A above middle C.Each octave higher doubles the frequency,and each of the 12 semitones in the octave increases the frequency in the same ratio.(a)What is this

一道指数英文数学题求解An orchestra tunes to a frequency of 440,which sounds the A above middle C.Each octave higher doubles the frequency,and each of the 12 semitones in the octave increases the frequency in the same ratio.(a)What is this 一道数学题大神求解! 一道数学题不会求解 求解一道抛物线数学题. 一道数学题求解 求解一道解析几何数学题 一道数学题求解速度 一道数学题,.,.求解,谢谢 一道高一指数幂运算数学题. 一道数学题,指数忘记怎么算了 八下数学题一道!求解!～～～ 数学题一道数学达人进如图 求解 一道数学题,学霸求解 求解一道数学题 要方程 求解一道SAT1的数学题 一道数学题,求解（下有图） 数学题一道(如图)求解 数学题求解(如图)一道