Acoustic transmission between air and water (a) consider an air-water interface for acoustic waves that are normally incident from the air side. what fraction of incident acoustic wave power is transmitted into the water? note that you can compute this by computing the fraction reflected, and the fraction transmitted is what is left over. (b) how about the opposite direction, from water to air? what fraction of normally incident power from the water side is transmitted into the air? (c) using your knowledge of anti-reflection coatings for electromagnetic waves, deter- mine the density, bulk modulus, and thickness of an acoustic anti-reflection coating that could be put on the air-water interface to eliminate reflections from the air side at a frequency of 400 hz. note that there is a range of possible solutions. (d) what kind of material would have these properties? a gas? a liquid? something in between? can you find any real material that comes close? note: if you think that you don't know a parameter that you need to know, then look it up.