A certain musical scale has has 13 notes, each having a different frequency, measured in cycles per second. In the scale, the notes are ordered by increasing frequency, and the highest frequency is twice the lowest. For each of the 12 lower frequencies, the ratio of a frequency to the next higher frequency is a fixed constant. If the lowest frequency is 220 cycles per second, then the frequency of the 7th note in the scale is how many cycles per second?	Pick
A) 220 * sqrt 2  B) 220 * sqrt (2^7)  C) 220 * sqrt (2^12)  D) 220 * the twelfth root of (2^7)  E) 220 * the seventh root of (2^12)
Let the constant be k.   F1 = 220   F2 = 220k   F3 = 220 k * k = 220 * k^2   F13= 220 * k^12   we know F13 = 2 *F1 = 2 * 220 2 * 1= 
<gadget id="calculator">2 * 1</gadget>
<output>2</output>
2 * 220= 
<gadget id="calculator">2 * 220</gadget>
<output>440</output>
440   440/220= k^12   k = twelfth root of 2   for F7...   F7 = 220 * k^6 ( as we wrote for F2 and F3)   F7 = 220 * (twelfth root of 2) ^ 6   F7 = 220 * sqrt (2)   The answer is 220 * sqrt 2.
<result>A</result>
A certain musical scale has has 13 notes, each having a different frequency, measured in cycles per second. In the scale, the notes are ordered by increasing frequency, and the highest frequency is twice the lowest. For each of the 12 lower frequencies, the ratio of a frequency to the next higher frequency is a fixed constant. If the lowest frequency is 220 cycles per second, then the frequency of the 7th note in the scale is how many cycles per second?