Is this pairing? Or doing two samples with unknown variances that are not equal? They want a 90% confidence interval.
Pesticides applied to an extensively grown crop can result inadverdent areawide air contamination. Ambient air samples were collected and alayzed at an orchard site for eac hof 11 days during the most intensive period of spraying. The levels of diazinon residue during the day and at night are recorded in the table (a whole list given). The researchers want to know if the mean diazinon residue levels differ from day to night.
So... we are given data to work with. Is this pairing? Or is it just your regular two populations? Thanks!!