Adiploid cell contains three pairs of homologous chromosomes designated c1 and c2, m1 and m2, and s1 and s2; no crossing over occurs. what possible combinations of chromosomes will be present in

Which statements explains what the fossil records indicates? check all that apply. a) earth is 4.5 billion years old b) many organisms have become extinct c) mammals have always existed on earth d) mass extinctions have occurred several times on earth e) the amount of water on earth has decreased over time?