Question: Noise Levels in Hospitals. In the hospital study cited in Exercise 19 in Exercise set 7-1, it was found that the standard deviation of the sound levels from 20 areas designated as casualty doors was \[\text{4}.\text{1}\] dBA and the standard deviation of 24 areas designated as operating theatres was 7.5 dBA. At a = \(0.05\), can you substantiate the claim that there is a difference in the standard deviations?