He measures the amount of radioactive uranium in the sample and compares it to the amount of radioactive lead. He then compares these amounts to the rate at which these two radioactive materials decay.

What is Rex most likely trying to figure out about the rock formation?
A.
its mass
B.
its density
C.
its age
D.
its volume
PLEASEEE HELP YOU GET 12 POINT

C.  its age

Explanation:

Rex is most likely trying to figure out the age of the rock formation. It is usually done by comparing the isotopic ratios of the daughter to the parent and their decay rates.

This is known as radiometric dating. Here an exact numerical age of the rock is usually obtained by measuring these isotopic ratio. The rate of decay serves as a clock to measure how far the radioactive material has decayed in time

My answer is letter d

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.