service agreement. A contract entered into for a contractor to provide some form of useful task for their employers in return for compensation. A service agreement can also be a feature offered along with a warranty for a product for the manufacturer to provide service or coverage of any costs of service in case the product malfunctions during a given period.
Euridice (1600) is the first surviving opera. The libretto was by Rinuccini, music by Peri, with some portions by Caccini. This was also significant in that it used recitative, a foundation of operatic storytelling. But--what was the first great opera? My vote is for Monteverdi's Orfeo, libretto by Striggio, premiered in 1607.
Written for the Teatro della Pergola in Florence, it was Verdi's tenth opera and first given on 14 March 1847. Macbeth was the first Shakespeare play that Verdi adapted for the operatic stage. Almost twenty years later, Macbeth was revised and expanded in a French version and given in Paris on 19 April 1865.