__ Ring, Inflatable for Helping Kids Float
Puzzle 5 of Science Fair Projects Piece of Cake Pack
Question is: __ Ring, Inflatable for Helping Kids Float
and the answer is: RUBBER
Word Meaning:
RUBBER — (uncountable, countable) Pliable material derived from the sap of the rubber tree; a hydrocarbon biopolymer of isoprene.
Definitions from Wiktionary.