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?

climate change and pollution

this would be a math

transformative rocks are the stones that emerge from the transformation of existing rock composes in a procedure called changeability, implies changing of structures. transformative rocks are shaped from alternate shakes that are changing a result of warmth or weight connected. one of this model is the earth developments that making rocks profoundly cover or crushed which will make the stones warmed and put under awesome weight. they are not softening but rather the minerals they are containing are changed synthetically that will shape transformative rocks. now and again different rocks are shaped when the others are near some liquid magma and getting warmed.