Answer:
All of us are exposed to radiation every day, from natural sources such as minerals in the ground, and man-made sources such as medical x-rays. According to the National Council on Radiation Protection and Measurements (NCRP), the average annual radiation dose per person in the U.S. is 6.2 millisieverts (620 millirem).
Explanation:
The ball isn't magnetic, therefore, the nail wasn't attracted towards the ball, but rather towards the magnet.
Answer:You didn't provide examples
Explanation: Groundwater can cause erosion under the surface as it moves through the soil. During the movement an acid is formed which what causes erosion and deposition.
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