<span>coal, oil shale, gemstones</span>
Answer:
The answer is "Performance continually increases as arousal increases".
Explanation:
The Inverted-U hypothesys, so named because the shape it reflects on a graph, indicates that a very low or high level of arousal can be detrimental for the performance of a task. This means that the best position is an intermedite point of arousal, in which there is both a little of excitement and stress associated with the task.
it would be fire to warm homes and Lumber to build homes.
As they both require use of wood which is from trees