I don't think so. And remember some items need two talents to craft.Is it possible for a player to attempt to use Craft to build a substandard version of a item if they don't have the requisite talent?
Well spotted.Lead the Way and Keep Watch (PHB p.145): Clarified that helping is not allowed.
ExactlyI was under the assumption that a sack is what the food is carried in. So your gear is the backpack, your food is in the sack, your water is in the waterskin, and your arrows are in a quiver. Each having no encumbrances if empty.