a function can be classified as one-to-one correspondence, one-to-many correspondence and many-to-one correspondence.

For a one-to-one mapping, all the elements of the domain R must have a unique element in the co-domain RFor a one-to-many mapping, an element of the domain R must have more than one element in the co-domain RFor a many-to-many mapping, all elements of the domain R must have a unique element in the co-domain R

Mappings can be classified as one-to-one, one-to-many, and many-to-one

A mapping of a set of domain R to another set of domain X is expressed as:

f: X→ R where:

X is the domain

R is the co-domain

For a one-to-one mapping, all the elements of the domain R must have a unique element in the co-domain RFor a one-to-many mapping, an element of the domain R must have more than one element in the co-domain RFor a many-to-many mapping, all elements of the domain R must have a unique element in the co-domain R

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It is an outlier because idk sorry

One unique triangle, because those angles add up to 180, and that's how many degrees there are in one triangle.