Here The data set is given as,

The mean of n observation is given as,

The mean is calculated as,

Arranging the given observation in ascending order,

Here n is 9 which is odd. Therefore median for the odd number of observations is calculated as,

Thus the median is 9.
Mode refers to the observation which occurs a maximum number of times in the given dataset.
Therefore the mode is 7.
The standard deviation of the given dataset is 4.71.