A trader pays three quarters of its own price at its usual stock. Each one it already holds beyond that, and each one in the same sale, lowers the price; a trader short of stock pays more, never more than its base price.
Study Table
+20Green tech points
3Science it costs
3Ticks2 with Researcher
2Energy per tick1 with Researcher
Each item can be studied once. Studying it at the Study Table uses the Science it needs; the item is kept.