17).

Inverse: if the two line segments are not in the same length then they are not congruent

Converse: if the two line segments have the same length, then they are congruent

Contrapositive: if its not congruent, then they are not in the same length

20).

Inverse: if the number does not end in either 0 or 5, then they are not divisible by 5

Converse: if the number ends in either 0 or 5, then it is divisible by 5

Contrapositive: if the number is not divisible by 5, then it does not end in either 0 or 5