PLEASE HELP, WILL MARK BRAINLEST TO WHO EVER ANSWERS FIRST The table below shows the half-lives of four radioactive materials. Radioactive material Half-lives Bismuth-212 60.5 seconds Sodium-24 15 hours Iodine-131 8.07 days Strontium-90 29 years Which of these materials will decay the slowest to one-fourth of its original amount? Bismuth-212 Sodium-24 Iodine-131 Strontium-90

Which conditions are necessary for natural selection to occur? select all of the answers that apply. a. inheritable adaptations vary among individuals. b. the population size is increasing. c. more individuals are born than can survive. d. fitness varies among individuals. e. the environment changes suddenly and drastically.

Plz ! cattle ranchers and dairy farmers rarely allow all of their animals to reproduce instead they practice selective breeding and only encourage the reproduction of animals with specific features. which of the following cows would a dairy farm most likely choose to reproduce? a. a cow that makes a lot of milk. b. a cow that can run quickly. c. a cow with a think, soft fur. d. a cow with large, strong hooves.

Apopulation of black bears depends on salmon from a stream for food. if a drought causes the stream to run dry one year, how will this likely impact the black bear population?