Which function is shown in the table below?

What is the common difference in the following arithmetic sequence? 7,3,-1,-5

100 points, hi, i’m not sure how to get the equation from the graph and table.

Bobby bought 1.12 pounds of turkey at a cost of 2.50 per pound. carla bought 1.4 pounds of turkey at a cost of 2.20 per pound. who spent more and by much?