Answer:
They came up with the term “radioactivity.”
They conducted experiments with uranium-containing minerals and pure uranium.
They discovered two new radioactive elements.
Step-by-step explanation:
As we know that the radioactivity is discovered by Marie and Curie and as per the experimental verification of the theory given by them we can say that rate of decay of a radioactive sample is directly proportional to the number of the radioactive same present at that time.
So it is given as

so here they also discovered two new radioactive substance apart from all the experiments related to the Uranium