Bongani owns and operates a fuel garage. He compiled the table below showing the number of litres of each type of fuel sold per month in 2020 .

\[

\begin{array}{llll|}

\hline \text{5}{l}{\text { Litres sold }} \\

\hline \text { Month } & \text { 93 unleaded petrol } & \text { 95 unleaded petrol } & \text { Diesel } \\

\hline \text { January } & 5501 & 2033 & 9402 \\

\hline \text { February } & 5327 & 1703 & 9333 \\

\hline \text { March } & 4861 & 1599 & 9471 \\

\hline \text { April } & 5428 & 2041 & 9567 \\

\hline \text { May } & 5500 & 2033 & 9602 \\

\hline \text { June } & 4899 & 2488 & 9312 \\

\hline \text { July } & 5423 & 2349 & 9322 \\

\hline \text { August } & 6011 & 1432 & 9550 \\

\hline \text { September } & 6547 & 2087 & 9400 \\

\hline \text { October } & 5203 & 2031 & 9566 \\

\hline \text { November } & 5671 & 1754 & 9410 \\

\hline \text { December } & 5002 & 1865 & 9500 \\

\hline

\end{array}

\]

**Question 1**

Give a fully labelled pie chart showing the relative contributions of each type of fuel to Bongani's total sales for the whole of \(2020 .\)

**Question 2**

Calculate the mean for the monthly number of litres of 93 unleaded petrol sold. Round off your answer to 2 decimal places. Show your workings.

**Question 3**

Calculate the median for the monthly number of litres of 95 unleaded petrol sold. Round off your answer to 2 decimal places.

**Question 4**

Calculate the interquartile range for the monthly number of litres of 95 unleaded petrol sold. Round off your answer to 2 decimal places. Show your workings.

**Question \(\mathbf{5}\)**

Calculate the range of the monthly number of litres of each type of fuel sold.

**Question 6**

Use a calculation or a tool like Excel to determine the standard deviation for the monthly number of litres of each type of fuel sold. Round off your answer to 2 decimal places.

**Question 7**

Bongani is offered a \(10 \%\) discount from his fuel supplier if he orders a certain type of fuel once a month, instead of weekly. Bongani would like to first test this by moving from weekly orders to monthly orders for one of type of fuel only.

Which type of fuel should Bongani order monthly for the trial? Briefly explain two reasons for your answer.