Answer:
Correct answer is: Due to interaction between Pacific and North American plate.
Explanation:
Mountain Redoubt is located in south Alaska. Mentioned mountain is in the vicinity of convergent plate boundary between North American and Pacific plate.
Convergent boundary means that those plates are <em>colliding</em>. One plate always slides beneath another, and in this case Pacific plate slides beneath North American. Area of collision is known as subduction zone.
Pacific plate is oceanic plate, and North American is continental plate. Oceanic plates <u>always slides</u> beneath continental ones. Reason for that is due to their density. Oceanic plates are denser, so they go under continental ones.
Pacific and North American plate interaction is typicall oceanic-continetal boundary where <em>earthquakes</em> (seismic activity) and <em>active volcanoes</em> are common. Some of the strongest earthquakes happened in this area. That was in 1964 in Prince William Sound in the south coast of Alaska. Magnitude was 9.2M, second strongest quake ever recorded in world's history.
<span>Platinum can be found in: Chromite bands
Chromite could be easily found in ultramafic layer of intrusive rocks and it contain several similar components as those that we could found in magma.
The black bands part of the chromite also carries several substance from platinum group metals.</span>
<u>Answer:</u>
<em>Anytime observations need to be clarified. When an unusual condition need to be shown for later reference.</em>
<u>Explanation:</u>
Instead of just recording the data the is sometimes important to be sketched out as the data observed is needed to be clarified and also sometimes there is an unusual condition that occurs and hence, it is important to sketch it so that it can be used for later reference.
<em>Therefore, when we are aware of the situation we need not sketch the data.</em>
Answer:
For the countour part: Map c, contour is 50m (the lines increases/decreases with 50 meters each step). Map b, need to see the whole map to decide.
