6. Using the natural frequency in question 5, what frequency does someone hear if the sound source is moving away from them at 25 m/s? Again, the speed of sound is 340 m/s. (10 points) 7. How many octaves are there between 27.5 Hz and 220 Hz? Show how you arrived at your answer. (10 points) 8. Explain why the field of sonography uses ultrasonic frequencies (higher than human hearing) instead of, say infrasonic frequencies (lower than human hearing). (10 points) 9. Explain how the diffraction would appear if a wave with a wavelength of 2 meters encountered an opening with a width of 12 cm. (10 points) 10. Explain what is meant by the tagline for the movie Alien: "In space, no one can hear you scream." (10 points) 0 ke? (10 points)