Question: How many acts are in the opera based on an 1820 poem by Alexander Pushkinhave, in which Mariya Matveyevna Stepanova created the lead soprano role?

Context articles: Elisabeth Söderström
The Cloud (poem)
Fête galante (Schierbeck)
Ruslan and Lyudmila (opera)
Sapho (Massenet)
Alice May
Karin Branzell
Emma Howson
Mariya Matveyevna Stepanova
Adelina Catalani

Anna Elisabeth Söderström {'1': ", '2': ", '3': 'CBE', '4': "} (married name Olow; 7 May 192720 November 2009) was a Swedish soprano who performed both opera and song, and was known as a leading interpreter of the works of Janáček, Rachmaninov and Sibelius.
 She was particularly well known for her recordings of the lead soprano roles in the three Janáček operas "Jenůfa", "Káťa Kabanová", and "The Makropoulos Affair", all of which received "Gramophone" Awards.
 The "Gramophone" critic John Warrack described her portrayal of Káťa Kabanová as "establishing by an infinity of subtle touches and discreet, sensitive singing the picture of Káta as the richest and most human character in the drama."
"The Cloud" is a major 1820 poem written by Percy Bysshe Shelley.
 "The Cloud" was written during late 1819 or early 1820, and submitted for publication on 12 July 1820.
 The work was published in the 1820 collection "Prometheus Unbound, A Lyrical Drama, in Four Acts, With Other Poems" by Charles and James Ollier in London in August 1820.
 The work was proof-read by John Gisborne.
 There were multiple drafts of the poem.
 The poem consists of six stanzas in anapestic or antidactylus meter, a foot with two unaccented syllables followed by an accented syllable.
Fête Galante is a 1930 Danish-language comic opera by Poul Schierbeck to a libretto by Max Lobedanz.
 It was performed seven times at the Royal Theatre, Copenhagen 1931-32 with the composer's wife Sylvia Larsen in the main soprano role, but then not revived until 1960.
Ruslan and Lyudmila (Russian: Руслан и Людмила , "Ruslan i Lyudmila") is an opera in five acts (eight tableaux) composed by Mikhail Glinka between 1837 and 1842.
 The opera is based on the 1820 poem of the same name by Alexander Pushkin.
 The Russian libretto was written by Valerian Shirkov, Nestor Kukolnik and N. A. Markevich, among others.
 Pushkin's death in the famous duel prevented him from writing the libretto himself as planned.
Sapho is a "pièce lyrique" ("lyric play", an opera in a declamatory style) in five acts.
 The music was composed by Jules Massenet to a French libretto by Henri Cain and Arthur Bernède, based on the novel of the same name by Alphonse Daudet.
 It was first performed on 27 November 1897 by the Opéra Comique at the Théâtre Lyrique on the Place du Châtelet in Paris with Emma Calvé as Fanny Legrand.
 A charming and effective piece, the success of which is highly dependent on the charisma of its lead soprano, it has never earned a place in the standard operatic repertory.
Alice May (1847 – 16 August 1887), sometimes known as Louise Allen, was an English singer and actress, perhaps best remembered as the creator of the soprano role of Aline in Gilbert and Sullivan's "The Sorcerer" (1877).
Karin Branzell (24 September 189115 December 1974) was a Swedish operatic contralto (sometimes described as a mezzo-soprano), who had a prominent career at the Metropolitan Opera, New York, and in Europe.
 Her very wide range enabled her to sing both contralto roles and the occasional soprano role.
 She was particularly noted for her singing of the music of Richard Wagner, in roles such as Ortrud ("Lohengrin"), Venus ("Tannhäuser"), Erda ("Das Rheingold" and "Siegfried"), Brangäne ("Tristan und Isolde"), and Brunnhilde ("Die Walküre").
 She was considered on a par with Margarete Klose and Kerstin Thorborg as a Wagnerian contralto.
 Amneris ("Aida"), Dalila ("Samson et Dalila"), Herodias ("Salome"), and Clytemnestra ("Elektra") were among her other renowned roles.
Emma Howson (28 March 1844 – 28 May 1928) was an Australian opera singer and actress primarily known as the creator of the principal soprano role of Josephine in the Gilbert and Sullivan comic opera "H.M.S. Pinafore".
Mariya Matveyevna Stepanova (Russian: Мария Матвеевна Степанова) (1811 or 1816 – 1903) was a Russian opera singer who created the leading soprano roles in "A Life for the Tsar", "Ruslan and Lyudmila", and "Dmitry Donskoy".
Adelina, sometimes Adelaide or Adele, Catalani (fl.
 1818–1832) was a Franco-Italian soprano.
 She is remembered today largely for the circumstances surrounding her performance of the lead soprano role in Gaetano Donizetti's first staged opera, "Enrico di Borgogna", in 1818.