What is the difference between an upstream and a downstream intercompany transaction?

How is the unrealized-profit holdback reflected on the parent's books under the equity method?

Besides sales/purchases, what other intercompany revenues and expenses are eliminated?

When is profit on an intercompany sale of an asset considered unrealized, and when is it realized?

Why are intercompany sales and purchases eliminated on consolidation, and what is the net effect on consolidated net income?

How does an unrealized-profit holdback affect the NCI for upstream vs downstream transactions?

Which basic accounting principles support eliminating intercompany sales and unrealized profit?