Understanding the type of knots that are allowed to be opened on Shabbos.
Is One Allowed to Cut a Pill or a Suppository in Half When They Want a Specific Size;
דבר דבר (Dabair Davar): If Something Is Not Allowed to Be Done on Shabbos, One Could Not Say They Will Be Doing It During...
putting up a hook with a suction cup or adhesive backing; important concepts how to work with a broken window;