Conifer tree is the tree that the leaf is slender like needle, it is evergreen tree more, material is general softer, some contain colophony , reason calls soft material again, its grows in elevation 100 ~ 1500 meters commonly, have economy and ornamental value.Conifers appeared 280 million years ago before any other trees.Conifers are believed to be the oldest trees on earth。
Fire resistance is where the amount of time that material has withstood a standard fire exposure whereas flame spread is the speed at which a flame spread along the surface of a specific material and is considered as the difference between fire resistance and flame spread.
Fire resistance is the resistance to fire that is for a particular specified time and is under circumstances of standard heat intensity. It will not structurally fail or else allow the transition of heat and also not permit the side away from the fire so as to become hotter than a temperature that is specified well.
Flame spread is described as the surface burning characteristics enhanced by building materials. It is the most tested property of the fire performance of a material.
Firefighters should be aware of the growth and spread of a fire as they face respiratory hazards in emergency situations which include oxygen deficiency, temperature elevation, smoke as well as toxic atmospheres. This can also affect both the physical and mental effects of the firefighter and would be worse if proper respirator precautions are not followed.
This indicates that firefighters are regularly exposed to certain concentrations of hazardous materials that include carcinogenic products such as carbon monoxide, benzene, sulphur dioxide, hydrogen cyanide, aldehydes as well as particulates.
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Light that appears white or nearly white to humans is made up of spectrum of visible light i.e. combination of violet, indigo, blue, green, yellow, orange and red.
Answer:
The temperature is staying the same. In the graph when it shows solid/liquid and liquid/gas, the temperature stays the same until it changes. This is because it reached it's melting point/vaporizing point. For example, a solid gets heated up, it then reaches it's melting point but it can't go higher than that because it isn't fully a liquid yet, once it's a liquid it will then continue to rise in temperature.
I don't think I put enough detail into that explanation but I hope this helps your problem.
Answer:
Soil erosion.
Explanation:
No-till plowing can be defined as a farming method or technique which typically involves planting crops (seedlings) without tilling the soil rather the farmer would only open a narrow or very shallow trench of sufficient depth and width to cover up the seedlings. Thus, the no-till plowing makes crop residues to be left on the soil and by extension preventing soil erosion through the absorption of water by the crop residues.
Hence, by leaving crop roots in the ground and stalks on the surface, no-till plowing helps prevent soil erosion.
Additionally, the water retention ability of no-till plowing is usually a boon to farmers because it slows down evaporation and serves as a good protection for drought-stricken environments.
