[Mister Micawber]

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Every piece of public writing is important, whether leaflets or reports-- but I think you've done a pretty good job, so I wouldn't worry about your grade. As for the headings... hmm. I'd say, arrange them so they look good together; try to be as consistent as you can; and follow the lower-case particles/articles/prepositions rule. That's the best you can do.

Good luck.
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