Respuesta :

  1. High/low notes have high/low frequency, not high/low amplitude.
  2. Heartz measures the number of waves per second, not per hour.
  3. Sounds do not travel in space because it's empty
  4. Sounds make our eardrum vibrate. The diaphragm is the muscle we use to breathe.
  5. Soft, pale materials are best for sound proofing because they absorb the waves.
  6. In the next paragraph, ultrasound and infrasound are inverted (ultra means "over, above" and infra means "below").