A Rock Sample Contains 1/4 Micrograms of the Parent Radioactive

question 57

Multiple Choice

A rock sample contains 1/4 micrograms of the parent radioactive isotope K-40 and 3/4 micrograms of its daughter isotope Ar-40. If the half-life of this decay is 1.25 billion years, how old is this rock?

• A) 5.00 billion years
• B) 3.75 billion years
• C) 1.25 billion years
• D) 2.50 billion years

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Definitions:

Preconventional Level

In Lawrence Kohlberg's theory of moral development, the earliest stage where moral reasoning is based on personal consequences and external rewards or punishments.

Moral Development

This refers to the way individuals acquire suitable behaviors and mindsets towards fellow community members, guided by the norms, rules, and laws of society and culture.

Punishments

Penalties or negative reinforcements given to decrease the likelihood of a behavior occurring again.

Empathic Parenting

A parenting approach that involves understanding and sharing the feelings of one's child, aiming to meet their emotional needs effectively.