<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: The increase in temperature of the nail after the three blows is 8.0636 Kelvins. The correct option is (d).
Explanation:
Kinetic energy of the hammer ,K.E.=

Half of the kinetic energy of the hammer is transformed into heat in the nail.
Energy transferred to the nail in one blow =

Total energy transferred after 3 blows,Q =
Mass of the nail = 15 g = 0.015 kg
Change in temperature =
Specif heat of the steel = c = 448 J/kg K



The increase in temperature of the nail after the three blows is 8.1 Kelvins.Hence, correct option is (d).
Which type needs the highest temperature to grow in?
Do all of the types make food the same way?
How long does it take for a specific type to make its seeds?
The other questions are all personal opinion
Thermal Expansion. best describes the increase in a materials volume
90 km/h is 25 m/s
the relative velocity when cars are traveling in opposite directions is the sum of the two
25+20= 45 m/s