7. On a certain day, the national average for the cost of a gallon of gasoline is $2.74. An official at a gasoline company selects an SRS of 25 gas stations and finds an average cost of $2.71 per gallon. Which of the following statements is true? O $2.74 and $2.71 are both statistics. $2.74 is a parameter and $2.71 is a statistic. $2.74 and $2.71 are both parameters. O $2.74 is a statistic and $2.71 is a parameter