What is the process by which plant roots absorb ammonium ions and nitrate ions for use in making molecules such as dna, amino acids, and proteins?

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?