The answer is sac. It
is a fungi that attacks elm trees and is carried by an insect called the elm
bark beetle. It hits the roots and
causes the tree to slowly deteriorate and eventually die due to lack of
nutrients once it is infected by this fungi.
Despite their frequency in the intertidal zone, in tide pools, sea urchins can be found at many different depths and in any habitats. They can also be found in nearly any ocean temperature. Sea urchins inhabit the polar seas as well as the warm tropics.
Con·cen·tra·tion
/ˌkänsənˈtrāSH(ə)n/
Learn to pronounce
noun
1.
the action or power of focusing one's attention or mental effort.
"frowning in concentration"
The predominant theory is from the geothermal gradient of the Earth. Being closer to the Earth's mantle, underground water tends to be of a higher temperature than surface water.
This is the best simplest answer to the question I'm aware of