Between "The Devil and Kate" and "Martha" which has more acts?
Martha (opera) Martha, oder Der Markt zu Richmond ("Martha, or The Market at Richmond") is a "romantic comic" opera in four acts by Friedrich von Flotow set to a German libretto by Friedrich Wilhelm Riese and based on a story by Jules-Henri Vernoy de Saint-Georges.
The Canterville Ghost (Knaifel opera) The Canterville Ghost (also "The Ghost of Canterville", Russian: "Кантервильское привидение" – Kantervíl’skoye privedénie, however usually spelt as "Кентервильское привидение" – Kentervíl’skoye prividénie; French: Le fantôme de Canterville, German: Das Gespenst von Canterville), an opera by the Russian composer Alexander Knaifel (Russian: Кнайфель) in three acts for 18 singers and chamber orchestra, also in an abridged version for two soloists and chamber orchestra.