Answer:
abierto
Step-by-step explanation:
In the verb: "abrir" we know it means "to open"
In Perfect Future tense, it would be Uds Abierto.
Reason: "The Indicative Future Perfect of abrir is used to talk about something that will have happened in the future after something else has already happened. For example, "habré abierto la puerta", meaning "I will have opened the door"(Ellaverbs.com).
It is an irregular past participle in Spanish.
Uds abierto translates to "They will have opened."