Answer:
Step-by-step explanation:
¿Devolverás Uds. los gafas de sol? ⇒ incorrect
The verb "devolver" conjugated in future tense is "devolverán"
"gafas" is plural feminine
"los" is plural masculine
"las" match with gafas
Then the correct sentence is:
"¿Devolverán Uds. las gafas de sol?
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