Biff has collected information on Toledo residential areas, roads, and traffic patterns, and has health information from the major local hospitals on emergency room visits for severe asthma attacks. He also has an air particulate model, which provides estimates of particulates in any part of the city at any time of day, by day of the week and season.

Questions:

1. Suggest how Biff can use GIS operations to separate his region into areas affected by higher traffic volume, and those with lower volume.
2. Categorize Biff's data in terms of type: point, line, area, or raster.
3. When Biff presents his results before a committee, he is asked to explain where he got the street data, and finds himself clueless: "From Dave," he says, but he doesn't even know Dave's job title or qualifications.

   Smelling blood, another member of the committee asks Biff what projection he's using to represent his spatial data. "Let us draw the curtain of charity over the rest of the scene" (to quote Mark Twain); Biff hasn't a clue.

   What did Biff neglect when assembling his data and doing his analysis?