Answer:
usually complements to the gas sales
Explanation:
Complementary products are those that their demand increases with the increased demand of other products.
Complementary products are usually used together. For example tea and sugar are consumed together, so an increase in tea consumption should result in an increase in sugar consumption.
In this scenario when the price of the convenience store products falls, their demand will increase. If there is an increase in gas sales too it is logical to conclude that the convenience store goods are complements of gas sales.
