The first harmonic of a series created by a standing air wave in a tube open at one end only is 35.4 Hz. If the length of the tube is 218 cm, calculate the speed of sound of the air. Use two digits of precision for your answer. A sound registers (5.10x10^1) decibels on a detector. What is the intensity in W/m? Assume the threshold of human hearing is 1.010-12 W/m. Use three significant figures for your answer.