Select three true statements regarding the infant's respiratory system.
1) Increased resiliency makes infants more tolerant of respiratory problems than older children.
2) Airway obstruction occurs sooner in infants than in older children.
3) Infants are obligatory nose breathers.
4) An adult's chest wall compliance is lower than an infant's.
5) A baby is born with all the alveoli he or she will ever have.