Two identical forward-facing loudspeakers are 33.6 cm apart. They are both connected to a signal generator that makes them vibrate in phase at a frequency of 2.12 kHz (Take the speed of sound as 340 m/s. Consider nonnegative angles only. Enter your answers from smallest to largest, starting with the smallest answer in the first answer blank below. Enter NONE in any remaining unused answer blanks.) (a) At what angles (in degrees), measured from the perpendicular bisector of the line joining the speakers, would a distant observer hear maximum sound intensity? smallest value (b) At what angles (in degrees) would such an observer hear minimum sound intensity? smallest value