A Sample of a Radioisotope Shows an Activity of 999

question 105

Multiple Choice

A sample of a radioisotope shows an activity of 999 disintegrations per minute due to beta decay.If after 1.10 years the activity is 952 disintegrations per minute, what is the half-life of this radioisotope?

• A)4.38 × 10^-2 yr
• B)11.4 yr
• C)0.25 yr
• D)15.8 yr
• E)9.1 yr

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Definitions:

Parental Income

The combined earnings of a child's mother and father or the income of a single parent.

Subliminal Suggestions

Subliminal suggestions refer to messages that are presented below the threshold of conscious awareness, influencing thoughts, feelings, or behaviors without conscious processing.

Independent Variable

The variable in an experiment that is manipulated or changed by the researcher to observe its effect on the dependent variable.

Dependent Variable

In an experiment, the variable being tested and measured, expected to change due to the influence of the independent variable.