1) An unfingered guitar string is 0.73 m long and is tuned to play E above middle C (330 Hz). (a) How from from the end of the string must a fret (and your finger) be placed to play A above middle C (440 Hz)? (b) What is the wavelength on the string of this 440-Hz wave? (c) What are the frequency and wavelength of sound in air at 20 degree's C by this fingered string? Answers: a) 0.18 m, b) 1.1 m c) 440 Hz and 0.78 m I am really stuck. All I can figure is that you incorporate L = v/2f.... and f = v/wavelength.... help me, please. 2) How many overtones are present within the audible range for a 2.14-m-long organ pipe at 20 degree's if (a) it is open (b) it is closed. Answers: a) 248 overtones, 249 overtones What I thought you could do was v/2L and v/4L.... 343/(2 x 2.14) = 80 and 40... not correct.