A sample survey of the opnions of the engineers of a small corportaion is conducted. The results of the sample indicate that the average salary is $45,987 and 60% have advanced degrees in either business or engineering. Which of the following statements are true? I. The average salary and the proportion of those with advanced degrees are statistics. II. The population f interest is all of the engineers in the industry. III. The results of the sampleshould be represented by symbols such as x-bar and p-hat.