<span>An indicator species is an organism whose presence, absence or abundance reflects a specific environmental condition. Indicator species can signal a change in the biological condition of a particular ecosystem, and thus may be used as a proxy to diagnose the health of an ecosystem. For example, plants or lichens sensitive to heavy metals or acids in precipitation may be indicators of air pollution. Indicator species can also reflect a unique set of environmental qualities or characteristics found in a specific place, such as a unique microclimate. </span>
<span>Magnitude. Intensity depends on the distance from the focus, but magnitude does not.</span>
Pretty sure it's outer core, lower mantle because the inner core is solid iron
The correct answer is: C: two and a half years. As a mater of fact, it started in May 1804 and lasted until September 1806. This expedition, also called Corps of Discovery Expedition was the first American expedition to cross what is now the western portion of the United States. Expedition was ordered by president Thomas Jefferson shortly after the Louisiana Purchase in 1803. The goals were to <span>explore and map the newly acquired territory, find a practical route across the Western part of the continent, and establish an American presence in this territory.</span>
