context: Mozart wrote his first symphony (KV 16) at the age of eight years in 1764 and his first opera at the age of 11 in 1767. He initially worked for Schrattenbach, Archbishop of Salzburg. When he died in 1771, he was succeeded by the harsh Hieronymus von Colloredo, a true tyrant even in the opinion of Wolfgang's father, Leopold. At Colloredo's courtyard, Mozart was in the same position as the kitchen staff. The relationship between Mozart and Colloredo was growing tense because of their different attitudes towards music. Colloredo's perspective was more productive, while Mozart's approach was artistic. Mozart felt that working under Colloredo was too restrictive for his artistic creation. Eventually, he decided to get rid of the Archbishop - that "man hatred" as he called Colloredo. He officially announced his resignation on May 10, 1781. [2]
question: At what age did Mozart compose his first symphony?
answers.text: eight years