I NEED HELP ASAP IM ON TIMER What did the Curies conclude about radioactivity based on their studies?
A. The amount of radioactivity is an extensive property because it varies as the amount of material varies.
B. The amount of radioactivity is an extensive property because it remains constant as the amount of material varies.
C. The amount of radioactivity is an intensive property because it varies as the amount of material varies.
D. The amount of radioactivity is an intensive property because it remains constant as the amount of material varies.

Marie Curie studied the radiation of all compounds containing the known radioactive elements, including uranium and thorium, which she later discovered was also radioactive. She also found out that:

- you can exactly measure the strength of the radiation from uranium;

- the intensity of the radiation is proportional to the amount of uranium or thorium in the compound - no matter what compound it is;

- the ability to emit radiation does not depend on the arrangement of the atoms in a molecule; it must be linked to the interior of the atom itself - a revolutionary discovery!

When she realized that some uranium and/or thorium compounds had stronger radiation than uranium, she made the following hypothesis: there must be an unknown element in the compound which had a stronger radiation than uranium or thorium. Her work aroused the interest of her husband, Pierre Curie, who stopped his own research on crystals and joined the "detective work" with his wife. And Marie was proven right

Explanation:Google

with this one i know the answer in craters one reason i looked it up and i learned about it there is my evidence

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.