Clifford likes dogs. He wondered how much dog owners spend on their dogs in a year. He hypothesized that dog owners spend more than $1000 a year on their dogs, on average. He sampled 75 dog owners in a local community and found that these 75 dog owners spent an average $1075 on their dogs in a year. Suppose sigma Subscript xequals$175.Assume that these 75 dog owners are representative of all dog owners in terms of amount spent on their dogs in a year. "What is the variable of interest?"