Consider the following statements based on the work of MarieCurie:
a. Impurities in pitchblende (an ore of uranium) are asufficient condition for increase in strength of emitted rays.
b. Diluted pure uranium (i.e., uranium plus impurities inpitchblende) is a sufficient condition for increase in strength ofrays
c. An unknown element was a sufficient condition for theincrease in strength of rays.
Use statements a, b, and c to summarize Marie Curie’s thoughtprocess that led to the discovery of radium.
