A 99-G Sample of Iodine-131 Is Stored for Exactly 3 Weeks

question 45

Multiple Choice

A 9.9-g sample of iodine-131 is stored for exactly 3 weeks.If the decay constant is 0.0861 day^-1,what mass of the isotope remains?

• A)0.15 g
• B)7.6 g
• C)1.6 g
• D)2.6 g
• E)5.5 g

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Definitions:

Standard Normal

An ordinary distribution with a 0 mean and a 1 standard deviation.

Random Variable

A variable with numerical outcomes derived from random occurrences.

Standard Normal

Refers to a normal distribution with a mean of 0 and a standard deviation of 1, used as a basis for comparing and standardizing normal distributions.

Random Variable

A variable whose outcomes depend on the results of a random phenomenon.