It takes approximately 48 to 72 hours for your level of hCG to double its levels. What this means for you depends on your body. If your level of hCG prior to pregnancy is 2 miU, it might take two to three days for it to double to 4 mIU and another two to three days for that to double to 8 mIU. This means it could take a week for the most sensitive pregnancy test to determine whether or not you a pregnant.
Navigation at Sea, History of. The first Western civilization known to have developed the art of navigation at sea were the Phoenicians, about 4,000 years ago (c. 2000 B.C.E. ). Phoenician sailors accomplished navigation by using primitive charts and observations of the Sun and stars to determine directions.
By their maritime trade, the Phoenicians spread the use of the alphabet to Anatolia, North Africa, and Europe, where it was adopted by the Greeks who developed it into an alphabetic script to have distinct letters for vowels as well as consonants.