6. List four limitations of conducting toxicity testing in order to determine the safe exposure level for humans. In other words, none of our existing methods are perfect

Explain how fossils scientists make discoveries about the lives of organisms and about how environments have changed over time. plz hurry up it time

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen

The diagram shows the results when two parents are crossed. the letters represent alleles for a trait that is controlled by three different genes. which best describes this inheritance pattern? multiple allele because a trait is controlled by three different genes polygenic because the offspring have alleles from both parents multiple allele because the offspring have alleles from both parents polygenic because a trait is controlled by three different genes