I just had this question. The answer is A. a battery
(2) U-238 is the radioisotope used in dating geological formations. Uranium-238 has a half-life of 4.46 billion years, which makes it suitable to date such old formations.
The other options do not have such long durabilities and half-lives.
opinion and belief mean a judgment that someone thinks is true. ... belief is used if the judgment is certain and firm in a person's own mind without regard to the amount or kind of evidence.
Solids,liquid, gas, plasma
I don't remember the other one