Which biconditional is not a good definition?

(1 point)
Responses

A whole number is odd if and only if the number is not divisible by 2.
A whole number is odd if and only if the number is not divisible by 2.

An angle is straight if and only if its measure is 180°.
An angle is straight if and only if its measure is 180°.

A whole number is even if and only if it is divisible by 2.
A whole number is even if and only if it is divisible by 2.

A ray is a bisector of an angle if and only if it splits the angle into two angles.
A ray is a bisector of an angle if and only if it splits the angle into two angles.

1 answer

All of the given biconditionals are good definitions and none of them are not a good definition.