Answer: OB
Explanation:
The empirical formula of an element is the simplest formula of an element which shows the ratios of atoms of the each element present in a molecule of a compound .
Liquid water turning into vapor.
Answer:

Explanation:
You can put that equation into a program like desmos on your browser and take a screenshot or use windows snippet tool.
Equation of a Wave: y = Acos(((2*pi)/B)x)
or

A = Amplitude
B= Wavelength
The amount of the 240 g sample of the radioisotope that will remain after 525 billion years is 7.5 g
<h3>How to the number of half-lives that has elapsed</h3>
- Half-life (t½) = 105 billion years
- Time (t) = 525 billion years
- Number of half-lives (n) = ?
n = t / t½
n = 525 / 105
n = 5
<h3>How to determine the amount remaining</h3>
- Original amount (N₀) = 240 g
- Number of half-lives (n) = 5
- Amount remaining (N) = ?
N = N₀ / 2ⁿ
N = 240 / 2⁵
N = 240 / 32
N = 7.5 g
Learn more about half life:
brainly.com/question/26374513
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