A sonic depth gauge is placed 4.3 m above the ground. An ultrasound pulse sent downward reflects off snow and reaches the device 0.023 seconds after it was emitted. The air temperature is 20C. (a) How far (in m) is the surface of the snow from the device? (Round your answer to at least three signicant figures.) :m (b) How deep (in m) is the snow? :m