What Is the Atomic Symbol for an Element with 39 ${ }_{81}^{89} \mathrm{Na}$

question 25

Multiple Choice

What is the atomic symbol for an element with 39 protons and 50 neutrons?

• A) \({ }_{81}^{89} \mathrm{Na}\)
• B) \({ }_{39}^{50} \mathrm{Y}\)
• C) \({ }_{39}^{89} \mathrm{Y}\)
• D) \({ }_{50}^{89} \mathrm{Sn}\)
• E) \({ }_{89}^{227} \mathrm{Ac}\)

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Definitions:

Estimate

An approximate calculation or judgment of the value, number, quantity, or extent of something.

Resource Constraint

A limitation or restriction on the availability of resources, such as time, money, or materials, that affects the ability to achieve an objective.

Master Schedule

A comprehensive timeline that outlines the major components and milestones of a project.

Network Diagram

A visual representation of a project's tasks and their dependencies on one another, often used in project management.