To estimate the average salary among people in a certain district, a marketing team obtains a simple random sample of 100 people from that district. The team sets up the following approximate 90% confidence interval, using a normal estimate, for the unknown average salary (in dollars annually) of the district: [41500,49750]

Approximately 90% of the people in the district have a salary in the interval
The procedure used to construct the interval works approximately 90% of the time.
For the normal estimate of 90% confidence to apply, the salary distribution in the population must be approximately normal.