To calculate the standard deviation and the interquartile range (IQR) of the data, we need to follow these steps:

Part 1: Standard Deviation

The formula for the sample standard deviation $s$ is:

$s = \sqrt{\frac{\sum (x_i - \bar{x})^2}{n - 1}}$

Where:

• $x_i$ represents each data point.
• $\bar{x}$ is the mean of the data.
• $n$ is the total number of data points (in this case, $n = 20$).

Part 2: Interquartile Range (IQR)

The interquartile range is the difference between the third quartile (Q3) and the first quartile (Q1):

$IQR = Q3 - Q1$

Let me calculate the standard deviation and IQR for the given data.