About 92 days are taken for 90 % of the material to <em>decay</em>.
The mass of radioisotopes (
), measured in milligrams, decreases exponentially in time (
), measured in days. The model that represents such decrease is described below:
(1)
Where:
- Initial mass, in milligrams.
- Current mass, in milligrams.
- Time constant, in days.
In addition, the time constant is defined in terms of half-life (
), in days:
(2)
If we know that
,
and
, then the time required for decaying is:






About 92 days are taken for 90 % of the material to <em>decay</em>.
We kindly invite to check this question on half-life: brainly.com/question/24710827
Answer:
blank A is 9. Blank B is 41. Blank C is 18. Blank D is 24
Using the normal distribution, it is found that there is a 0.877 = 87.7% probability of a bulb lasting for at most 569 hours.
<h3>Normal Probability Distribution</h3>
The z-score of a measure X of a normally distributed variable with mean
and standard deviation
is given by:

- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
The mean and the standard deviation are given, respectively, by:

The probability of a bulb lasting for at most 569 hours is the <u>p-value of Z when X = 569</u>, hence:


Z = 1.16
Z = 1.16 has a p-value of 0.877.
0.877 = 87.7% probability of a bulb lasting for at most 569 hours.
More can be learned about the normal distribution at brainly.com/question/24663213
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The answer is D, on a Graph, no two points can meet when drawn Vertically
Answer:
24
5.49
Step-by-step explanation: