Three statements are given, followed by four conclusions numbered I, II, III and IV. Assuming the statements to be true, even if they seem to be at variance with commonly known facts, decide which of the conclusions logically follow(s) from the statements.

Statements:
Some coolers are mixers.
Some mixers are scissors.
Some scissors are knives.

Conclusions:
I. Some knives are mixers.
II. Some scissors are coolers.
III. Some knives are coolers.
IV. No knife is a mixer.