4. A scientist finds a rock with old microfossils in it, likely from around 4 billion years ago. Which radioactive isotope should the scientist use to determine the age of the sample and why? (
se fosse uma pedra com 4 bilhoes de anos qual isotopo deveria de usar e porque?)

U-238

Explanation:

the half-life of uranium-238 is about 4.5 billion years

the dna molecules have a negative charge because of the phosphate groups in their sugar-phosphate backbone, so they start moving through the matrix of the gel towards the positive pole. power is turned on and dna fragments migrate through gel (towards the positive electrode).

explanation:

fossil's are like over rated rocks like low key not gonna lie i don't get why we can't just call them old rocks like for real i mean i call my grandpa and grandma that smh