⁹⁰ Sr Is a Radioactive Isotope That Decays by Beta-

question 29

Multiple Choice

⁹⁰ Sr is a radioactive isotope that decays by beta- decay. Its daughter nucleus is

• A) "⁸⁶ Kr."
• B) "⁸⁹ Y."
• C) "⁹⁰ Y."
• D) "⁸⁹ Rb."
• E) "⁸⁸ Rb."

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Definitions:

Hard-to-classify Child

A child whose behavior, needs, or characteristics do not neatly fit into conventional categories or expectations.

Slow-to-warm-up

Refers to a temperament observed in some children who tend to be cautious and less adaptive in new situations but gradually become more comfortable with time.

Responsiveness

The quality of reacting quickly and positively to changes or stimuli.

Still-face Technique

A research experiment where a caregiver maintains a neutral, unresponsive face towards an infant, observing the child's response to the lack of social engagement.