Answer:
Prepositional phrase is 'on both hands' and the preposition is 'on'.
Step-by-step explanation:
Prepositions are those words that shows the positioning of the nouns, indicating the relation of the noun and the other parts of the sentence. They are normally placed before the nouns, so that they will show the position of the object/ noun/ pronoun.
Prepositional phrases are those words or group of words that has a preposition and a noun in the end.
So, from the above sentence, the preposition is "on" and the prepositional phrase is "on both hands" as the word "both hands" constitute the object/ noun.