<h2>
Answer: U-238</h2>
Explanation:
Let's begin by explaining that for radioactive geological dating (also called radioisotope dating) in which radioactive impurities were selectively incorporated when the fossil materials were formed, it is very useful to compare it with a naturally occurring radioisotope having a known half-life.
Now, taking into account that the <u>fossils are millions and millions of years old, radioisotopes are needed that exceed this measure.
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To understand it better:
The longer the half-life of a radioisotope, the greater its utility for estimating fossil ages or geological formations.
In this sense, uranium-238 (U238) has a half-life of 4,470 million years, therefore, it is among the most commonly used radioisotopes for fossil and geological dating.
Answer:
A force is a push or pull that acts upon an object as a result of that objects interactions
Explanation:
A. Move the candle to the right, or the focal point to the left.
For a convex lens, the closer an object is to the focal point, the larger it’s image is (and therefore the greater the magnification is). The two ways you could make the candle be closer to the focal point are to move the candle to the right, or the focal point to the left.