Earth’s atmosphere, oceans, and continents began to form during the first several hundred years of (1 point) a. precambrian time b. the paleozoic c. the mesozoic era < - d. the cenozoic era 8. during the devonian period, animals that could live on land began to evolve. these animals still spent part of their lives in the water. what were these animals called? a. trilobites b. reptiles < - c. amphibians d. dinosaurs

Me i dont know what to do! the table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 10 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.