Waiting for a pregnancy test result can seem to take forever. The first week is often filled with confusion, hope, and worry. This article explains why you may not get a positive test in week 1, what ...

At head of title: DK Smithsonian. "The ultimate visual guide to the discoveries that shaped the world"--Cover. Before science began (2.5 MYA -- 799 C.E.) : Early metallurgy ; The story of the wheel ; ...