It is a heterogeneous mixture <span>
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The periodic table of elements is divided into columns and rows. The vertical columns represent the groups while the horizontal rows represent the periods. A group of elements usually have similar physical and chemical properties. The first column of the periodic table is made up of 7 elements including SODIUM.
1. The name of the element chosen is sodium and its chemical symbol is Na.
2. Sodium is a metal and thus it has metallic properties.
3. Sodium belongs to group one elements whose family name is ALKALI METALS.
4. The neutral atom of sodium is made up of 11 protons, 11 electrons and 12 neutrons.
Cs -137 has a half life of about 30 years. If 60 years pass, there is two half lives passed so 1/2 * 1/2= 1/4. Take 1/4 and multiply it with the mass given:
(1/4)*20mg=5mg left
Answer: plate
Explanation: Plates grinding past each other in opposite directions create faults called transform faults. Powerful earthquakes often strike along these boundaries. The San Andreas Fault is a transform plate boundary that separates the North American Plate from the Pacific Plate.
A is the correct awnser Beacuse it ether right kne
