Final answer:
Upon finding Juliet 'dead,' the Capulets react with immense shock and grief, mourning the loss with distraught lamentations.
Step-by-step explanation:
When the Capulets discover Juliet lying 'dead', their immediate reaction is one of utter shock, disbelief, and profound grief. Lord and Lady Capulet, along with the Nurse, express their devastation through exclamatory statements of sorrow and confusion. They are engulfed in the tragedy of losing their only daughter, and their response is a mix of loud lamentations and despair, showcasing the strong parental love they hold for Juliet which, in the chaotic events of the play, is often overshadowed by their wish to control her destiny.