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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Associative property of addition
I believe the answer is 88 because the 120 will create a straight angle which is 180. Then you do 180-120=60. This is the measure I the left angle. Now your answer will be 88
37.5*0.010=.375 (or press % button on calculator)
80*.375=30
Answer:
Step-by-step explanation:
1/9 of the camp means it has 9 parts the whole thing (each 1/9)
1/3 of an hour for 1 part and
for 9 parts we have
1/3 *9 = 9/3= 3 hours