$($a$)$ Using the dataset provided $($Appendix C$),$ determine whether, statistically, there is a difference between the

sales made on self$-$service checkouts and staff operated checkouts over the $6-$month trial run. Include a

screenshot of the analysis in your response. Justify the analysis approach used.

$($b$)$ Jordan is concerned that customers will be reluctant to use the self$-$service checkouts. Drawing on your

results, advise Jordan if this is the case.