Radioactivity: a Sphere Made of a Radioactive Isotope Initially Has

question 79

Multiple Choice

Radioactivity: A sphere made of a radioactive isotope initially has a mass of 6.88 kg. The half-life of this isotope is 1.34 h, and it decays by β^- emission. At the end of 2.68 h, what is the mass of this sphere?

• A) 6.88 kg
• B) 3.44 kg
• C) 1.72 kg
• D) 2.53 kg

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Definitions:

Stress

A psychological and physical reaction to certain life events or situations that can disrupt an individual's balance.

Cross-cultural Variability

The diversity in norms, values, practices, and behaviors observed among different cultures, highlighting the variability of human experience and social organization.

Parenting Behaviors

Parenting behaviors involve the strategies and actions used by parents or guardians in raising their children, which affect the child's development and socialization.