The table shows the soil density of several soil samples at different depths. Write the quadratic regression equation that models the data. Let x = depth below the surface and let y = soil density. Use the equation to estimate the soil density of a sample at a depth of 20 m. Show your work.

Me max recorded the heights of 500 male humans. he found that the heights were normally distributed around a mean of 177 centimeters. which statements about max’s data must be true? a) the median of max’s data is 250 b) more than half of the data points max recorded were 177 centimeters. c) a data point chosen at random is as likely to be above the mean as it is to be below the mean. d) every height within three standard deviations of the mean is equally likely to be chosen if a data point is selected at random.