There are $n$ observations and all of them are negative numbers. The ascending order of these observations is $x_1, x_2, \ldots . x_n$. If the signs of the first term and last term in that order are changed, then the range of the data is

The mean deviation from the mean for the observations $1,3,5,7,11,13,17,19,23$ is

The mean deviation from the mean of the discrete data $1,3,4,7,11,18,29,47,78$ is

If $\bar{x}$ is the mean of $n$ observations $x_1, x_2, \ldots ., x_n$ then the mean of the absolute deviations of these observations from $\bar{x}$ is