According to data from the 2010 United States Census, 11.4% of all housing units in the United States were vacant. Suppose Maria, a researcher, takes a random samiple of 200 housing units in the United States and finds that 15 are vacant. Let p represent the sample proportion of housing units that were vacant. What are the mean and standard deviation of the sampling distribution of p? Provide your answer rounded to three decimal places. mean: ___ standard deviation: __