Update 5-combining-them-all.mdx

Author: Meg528

docs/30-simple-queries/5-combining-them-all.mdx

@@ -33,7 +33,7 @@ db.books.aggregate([
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-👐 Get 15 books from 1985 with 150 pages. Show only the `title`, `year`, `totalInventory` and `available` books. If you don't remember which fields we have, you can refer to [the sample document](/docs/simple-queries/project).
+👐 Get 15 books from 1985 with 150 pages. Show only the `title`, `year`, `totalInventory`, and `available` books. If you don't remember which fields we have, you can refer to [the sample document](/docs/simple-queries/project).
 
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