90° is the correct answer
The percentage of the radioactive isotope left is 25.0000%.
<h3>What is the half life?</h3>
The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.
Now;
We are told that;
Half life (t1/2) = 55 days
Time taken (t) = 115 days
Ratio of isotope remaining = N/No
Thus;
N/No = (1/2)^t/t1/2
N/No = (1/2)^115/55
N/No = (1/2)^2
N/No =1/4
Hence, the percentage = 1/4 * 100/1 = 25.0000%
Learn more about half life of an isotope:brainly.com/question/16387602
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Lol another one?
So I looked at the graphs and the only one that actually even reaches 75 is the dotted one on the left. The one in the middle obviously doesn't go anywhere and the one on the right goes to 65, not 75.
Answer:
A. 14
Step-by-step explanation:
Okay, so the square is 25 and the circle is 39.
For example, if you take out the square from the circle, that leaves the shaded areas.
39-25=14
14 is your answer.
Cheers!
Answer:
3rd one
Step-by-step explanation:
2l + 2w = P
2w = P - 2l
w = P - 2l / 2
