The relationship between the number of popcorn and drinks is linear relationshipThe responses are;(a) Please find attached the required graph created with MS Excel(b) From the graph, we have that as the number of bags of popcorn Judy buys increases, the number of drinks decreases linearlyReasons:The given parameter are;Amount Judy took with her to spend on popcorn and drinks = $30Price of each bag of popcorn = $5Price of each drink = Half the price of a bag of popcorn∴ The price of each drink = (a) Let X represent the number of bags of popcorn Judy buys and let Y represent the number of drinks she buys, we have;5·X + 2.5·Y = 302.5·Y = 30 - 5·XWhich gives;Y = 12 - 2·XUsing the above equation, the graph of popcorn and drinks bought by Judy is plotted with MS Excel and attached here(b) The data in the graph are presented as followsThe point corresponding to the y-intercept is the point that gives the maximum number of drinks Judy can buy if she does not buy popcorn is 12 drinks. The number of drinks she can buy reduces by 2 for each bag of popcorn she buys, such that she can buy 6 bags of popcorn and no drinks which is the x-intercept.