Which one of the following is an example of negative side effect? $8,500 paid to a marketing consultant to help decide whether or not to start a new product line $1.5 million building used for a project that would rent for $100,000 otherwise $1,800 increase in comic book sales if a store commences selling puzzles $4,500 reduction in comic book sales if a store commences selling comic movies $1,500 paid to repair a machine last year