Uncertainty is defined as: Group of answer choices After an order is placed, it usually takes time (lead time) to receive the goods. Inventory can be used to ensure business continuity during these delays. Lead time, demand, supply, and other supply chain characteristics may be subject to uncertainty; inventory is then maintained as a buffer to hedge against this uncertainty. A pure lean approach, i.e. "one unit at a time at a place where a user needs it, when (s)he needs it" typically incurs lots of costs in terms of logistics. None of the above