The <span>era that is know as the age of mammals is the </span><span>Mesozoic
period.
Answer: Letter D
Hope that helps. -UF aka Nadoa</span>
<span>Lithium atoms have one valence electron, where as oxygen atoms have six. Lithium atoms tend to give up their single valence electrons, and oxygen tends to gain two valence electrons from other atoms, like lithium. They do this so they will have filled valence shells. hope this answers your question :)</span>
C3H6 and CH4
The empirical number is found by looking at the ratio of the numbers. For example, H20 and H402 have the same empirical formula because the ratio remained similar. 2 H to 1 O.
The nitrogenous bases on the two strands of DNA pair up, purine with pyrimidine (A with T, G with C), and are held together by weak hydrogen bonds. Watson and Crick discovered that DNA had two sides, or strands, and that these strands were twisted together like a twisted ladder -- the double helix.Mar