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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The equivalents of the given compound inequality are x > 3 and x ≤ 5.2 OR 3 < x ≤ 5.2
<h3>Solving inequalities </h3>
From the question, we are to determine the equivalent form of the compound inequality
We will solve the given compound inequality
The given inequality is
−22 > −5x − 7 ≥ −33
We can write that
−22 > −5x − 7 AND −5x − 7 ≥ −33
Solving −22 > −5x − 7
5x > -7 +22
5x > 15
x > 15/5
x > 3
Also,
Solve −5x − 7 ≥ −33
−5x ≥ −33 +7
-5x ≥ -26
x ≤ -26/-5
x ≤ 5.2
Hence, the equivalents of the given compound inequality are x > 3 and x ≤ 5.2 OR 3 < x ≤ 5.2
Learn more on Inequalities here: brainly.com/question/20356565
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To find the GCF:
-- List the factors of the first number.
-- List the factors of the second number.
-- Make a short list of the factors that show up for BOTH numbers.
-- Find the biggest number on the short list.
Factors of the first number (99): <u>1</u>, 3, 9, <u>11</u>, 33, 99 .
Factors of the second number (121): <u>1</u>, <u>11</u>, 121 .
Short list (factors that show up for both numbers): 1, 11
Biggest number on the short list: <em>11</em>
<span>a.
The radius of earth is about 6400 kilometers. Find the circumference of
a great circle.
Circumference = 2π(radius) = 2π(6400 km) = 40.212,39 km
b. Write an equation for the circumference of any
latitude circle with angle theta
As stated, </span><span><span>the
length of any parallel of latitude (this is the circumference of corresponding circle) is equal to the circumference of a
great circle of Earth times the cosine of the latitude angle</span>:
=> Circumference = 2π*radius* cos(Θ) = 2 π*6400km*cos(Θ) = 40,212.39 cos(Θ)
Answer: circumference = 40,212.39 cos(Θ) km
c. Which latitude circle has a
circumference of about 3593 kilometers?
Make </span><span><span>40,212.39 cos(Θ)</span> km = 3593 km
=> cos(Θ) = 3593 / 40,212.39 = 0.08935 => Θ = arccos(0.08935) = 84.5° = 1.48 rad
Answer: 1.48
d. What is the circumference of
the Equator?
</span>
For the Equator Θ = 0°
=> circumference = 40,213.49cos(0°) km = 40,212.49 km
Answer: 40,212.49 km
