There Are Two Letters X and Y

question 15

Multiple Choice

There are two letters X and Y.If repetitions such as XX are permitted,how many two-letter permutations are possible?

• A)2
• B)4
• C)6
• D)8

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Definitions:

Dipeptide

A molecule consisting of two amino acids linked together by a single peptide bond.

Emulsification

The process of breaking down large fat droplets into smaller ones, typically using bile acids, which increases the digestive enzymes' access to the fats.

Micelle Formation

The self-assembly of amphiphilic molecules into spherical structures in aqueous solutions, important for the absorption of fat-soluble vitamins and lipids.

Lipids

A diverse group of naturally occurring molecules that include fats, oils, waxes, and certain vitamins, serving as energy storage and important cell membrane components.