If a Rock Started with 1,000 Atoms of a Parent

question 10

Multiple Choice

If a rock started with 1,000 atoms of a parent but now contains 250 atoms, how many half lives have passed?

• A) .25 half lives
• B) .5 half lives
• C) 1 half life
• D) 2 half lives
• E) there is no way to tell

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Definitions:

Trained Therapist

A professional who has received specialized education and training to provide therapy to individuals or groups.

Group Therapy

A form of psychotherapy involving a group of patients led by one or more therapists, focusing on interpersonal interactions and communication.

Self-help Group

A group of people who share a common condition or difficulty, who gather together to discuss their experiences, offer support, and provide mutual aid.

Minority Groups

Social groups that are differentiated from and often subordinated to the dominant group in a society based on characteristics like ethnicity, race, sexuality, or economic status.