Understanding the logic between mixing horseradish and mayonnaise as opposed to baby cereal, etc.
How to Remove Gum When It Is Stuck in One's Hair, and How to Remove a Band-Aid;
How much time is needed before or after shabbos to say it is "שכר שבת בהבלעה" (shabbos earnings included with weekday earnings).
a quick review of all types of knots that are allowed to be open on Shabbos;