Question: A Life for the Tsar is a  Russian libretto with four acts, Tosca an Italian libretto has how many acts?
Sentence (from "The Snow Maiden"): The Snow Maiden (subtitle: A Spring Fairy Tale) (Russian: Снегурочка–Весенняя сказка , "Snegúrochka–Vesennyaya Skazka") is an opera in four acts with a prologue by Nikolai Rimsky-Korsakov, composed during 1880–1881.
Relevant evidence: No