ASK YOUR HCG QUESTIONS HERE. In most normal pregnancies at hCG levels below 1,200 mIU/ml the hCG usually doubles every 48-72 hours. At levels below 6,000 mIU/ml the hCG levels normally increase by at least 60% every 2-3 days, though increases between 50-60% can sometimes still be seen in normal pregnancies.SK YOUR HCG QUESTIONS HERE. In most normal pregnancies at hCG levels below 1,200 mIU/ml the hCG usually doubles every 48-72 hours. At levels below 6,000 mIU/ml the hCG levels normally increase by at least 60% every 2-3 days, though increases between 50-60% can sometimes still be seen in normal pregnancies.
The thin, outermost layer of the earth is called the crust. It makes up only one percent of the earth's mass. The continental crust is thicker than the oceanic crust. It can range from 25 km thick at the edges to 70 km thick near the center. The oceanic crust on the other hand is only about 7 km thick and considerably more dense.
The concept of plate tectonics was formulated in the 1960s. According to the theory, Earth has a rigid outer layer, known as the lithosphere, which is typically about 100 km (60 miles) thick and overlies a plastic layer called the asthenosphere. The lithosphere is broken up into about a dozen large plates and several small ones.