The discovery and isolation of radium in uranium ore (pitchblende) by Marie Curie sparked the development of uranium mining to extract the radium, which was used to make glow-in-the-dark paints for clock and aircraft dials. This left a prodigious quantity of uranium as a waste product, since it takes three tonnes of uranium to extract one gram of radium. This waste product was diverted to the glazing industry, making uranium glazes very inexpensive and abundant. Besides the pottery glazes, uranium tile glazes accounted for the bulk of the use, including common bathroom and kitchen tiles which can be produced in green, yellow, mauve, black, blue, red and other colors.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who isolated radium in uranium core?
Ah, so.. unanswerable

Works published since 1857 have received alternative catalogue designations instead of opus numbers. The present standard musicological reference for Chopin's works is the Kobylanska Catalogue (usually represented by the initials 'KK'), named for its compiler, the Polish musicologist Krystyna Kobylanska.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Pieces published after what year stopped receiving opus numbers?
Ah, so.. 1857

There are several academic libraries and archives in Paris. The Sorbonne Library in the 5th arrondissement is the largest university library in Paris. In addition to the Sorbonne location, there are branches in Malesherbes, Clignancourt-Championnet, Michelet-Institut d'Art et d'Archeologie, Serpente-Maison de la Recherche, and Institut des Etudes Iberiques. Other academic libraries include Interuniversity Pharmaceutical Library, Leonardo da Vinci University Library, Paris School of Mines Library, and the Rene Descartes University Library.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): In what arrondissement is the Sorbonne library in Paris located?
Ah, so..
5th