1. What beat frequencies are possible with tuning forks of frequencies 256, 259, and 261 HzHz ?

2. For years, marine scientists were mystified by sound waves detected by underwater microphones in the Pacific Ocean. These so-called T waves were among the purest sounds in nature. Eventually the researchers traced the source to underwater volcanoes whose rising columns of bubbles resonated like organ pipes. A typical T wave has a frequency of 7 HzHz.

Knowing that the speed of sound in seawater is 1530 m/sm/s, find the wavelength of a T wave. Express your answer to three significant figures and include the appropriate units.

3. A bat flying in a cave emits a sound and receives its echo 0.09 ss later. Find the distance to the wall of the cave. Express your answer to two significant figures and include the appropriate units.