It would most likely be the last one. Erosion is effectively the process of natural forces breaking down rock or soil, which allows it to move from place to place with the aid of forces like wind or water. I would say the answer would be the first one, but it only says rock, while erosion can affect more than just rocks. Hope this helps.
Information from deep-ocean exploration can help predict earthquakes and tsunamis and help us understand how we are affecting and being affected by changes in Earth's environment. Ocean exploration can improve ocean literacy and inspire young people to seek careers in science, technology, engineering, and mathematics.
Set this up as
10 = 40 (1/2)t/28
and solve for t in years.
10/40 = (1/2)t/28
log(0.25) = (t/28) log(0.5)
t = 28 log(0.25) / log(0.5) years = 56 years
Test the answer:
56 years = 2(28 years) = 2 half-lives, so the remaining amount should be 1/2 of 1/2 of the initial amount, i.e. 1/4 of the initial amount, and 10 mg = 1/4 of 40 mg.
The correct answer is (B) They are both Northern Hemisphere, warm-temperate forests. Although Appalachian (U.S.A.) and Southwestern Caucasus (Russia) have common origins, both northern hemisphere warm-temperature Tertiary forests, they have developed differently. The similarities also include the species-to-genus, species-to-families ratios and the floristic composition.
