Solve the Problem $\text { If } \sum a _ { n } \text { is a convergent series of nonnegative terms, what can be said about } \sum a _ { n } a _ { n + 1 } \text { ? }$

question 445

Multiple Choice

Solve the problem.
- $\text { If } \sum a _ { n } \text { is a convergent series of nonnegative terms, what can be said about } \sum a _ { n } a _ { n + 1 } \text { ? }$

• A) Always diverges
• B) May converge or diverge
• C) Always converges

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Definitions:

Upper Mantle

The upper mantle refers to the section of the Earth's mantle situated just beneath the Earth's crust, extending down to about 660 kilometers below the Earth's surface. This region is significant for its role in tectonic movements and the convection currents that drive plate tectonics.

Earth's Layers

The division of the Earth into distinct layers including the crust, mantle, and core, each with its own properties and composition.

Surface

The outermost or uppermost layer of an object or area which is in direct contact with the environment.

Upper Mantle

The upper mantle refers to the portion of the Earth's mantle that lies just beneath the crust and extends to depths of about 660 kilometers, involved in tectonic processes.