Why are the average masses on the periodic table rarely whole numbers even though it is impossible for an atom to weigh a fraction of an a. m.u.?

Which of the following is one of the four conditions necessary for natural selection to occur in a population? fewer organisms are born than the habitat can support mutation does not occur organisms have identical characteristics variation is inherited

~fourth largest plate ~includes parts of the indian and atlantic oceans ~subducts below the eurasian plate on the west side ~ the arabian and somali plates form boundaries with it what is the name of the tectonic plate described above? a) african plate b) eurasian plate c) north american plate d) indo- australian plate

Use the drop down menus to match each example to the fossil topic discussed then to show how the fossil record gives evidence of evolution