a.) Describe how the first fundamental frequency changes when you change the length of an closed ended tube system . Write the general equation for length of an closed ended tube system as a function of frequency and harmonic number, n . b.) In a closed ended tube system , describe where the nodes and anti-nodes are located when a standing ( resonant ) sound wave is formed . Try to describe this for the general case . c.)Does the speed of sound increase or decrease with air temperature ? In a few sentences explain why .