The Sizes of Two Matrices a and B Are Given $2 \times 1$

question 25

Multiple Choice

The sizes of two matrices A and B are given. Find the sizes of the product AB and the product BA, whenever these
products exist.
-A is $2 \times 1$ , and $B$ is $1 \times 1$ .

• A) \( \mathrm{AB} \) does not exist; \( 1 \times 2 \)
• B) \( 2 \times 2 ; 1 \times 1 \)
• C) \( 1 \times 2 ; 1 \times 1 \)
• D) \( 2 \times 1 \); BA does not exist.

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Definitions:

Endothermic

Refers to a process or reaction that takes in energy from the environment, usually as heat.

Exothermic

A chemical process that releases energy to its surroundings, usually in the form of heat.

Free Radical Chain Reaction

A sequence of reactions where free radicals, generated in an initial step, propagate and react with other molecules to produce stable products, typically involving a chain initiation, propagation, and termination step.

Bond Dissociation Energies

The energy required to break a specific chemical bond in a molecule into two parts, under specified conditions.