G: The correct pronunciation for the GNU library program "calibre" is typically "cal-uh-ber."

G: Yes, Google's advanced search operators allow you to refine your search. For example, you can use "site:" to search within a specific site or "filetype:" to find specific file types. Is there a particular advanced search rule you're interested in?

G: A common substitute for sour cream in recipes is plain yogurt. You can also use Greek yogurt for a thicker consistency. Alternatively, buttermilk or a mixture of milk and lemon juice or vinegar can work in certain recipes.