The curies took pure uranium and a uranium-containing substance. when they measured the amount of radioactivity, there was more in the uranium-containing substance than the pure uranium. which idea did the curies most likely develop? a there are more radioactive substances than uranium. b radioactivity is magnified by mixed substances. c the date of the material varied between the pure substance and mixed substance. d the half-life of uranium in a mixed substance is less than pure uranium.
