Structure of the Earth easily than does the upper mantle (chemical changes within the mantle may also be important). The viscosity of the mantle ranges between 10 and 10 Pa·s, depending on depth. In comparison, the viscosity of water is approximately 10 Pa·s and that of pitch is 10 Pa·s. The source of heat that drives plate tectonics is the primordial heat left over from the planet’s formation as well as the radioactive decay of uranium, thorium, and potassium in Earth’s crust and mantle. The average density of Earth is . Because the average density of surface material is only around , we must
What the Bleep Do We Know!? Theater in Portland, Oregon, where it was filmed. Within several weeks, the film had appeared in a dozen or more theaters (mostly in the western United States), and within six months it had made its way into 200 theaters across the US. According to the makers of the film, "Bleep" is an expurgation of "fuck". William Arntz has referred to the film as "WTFDWK" in a message to the film's street team. The Institute of Noetic Sciences, a New Age research organization that "explores phenomena that do not necessarily fit conventional scientific models", has supported "What the Bleep Do We