Why is continental crust lower in density than seafloor crust?
A) Continental crust is made of rock, while seafloor crust has more metals.
B) Continental crust is made from volcanic rock called basalt, which is lower in density than what the seafloor crust is made from.
C) Continental crust is made from remelted seafloor crust and therefore only the lower-density material rises to form it.
D) Continental crust is actually denser than seafloor crust.
E) Seafloor crust is more compact due to the weight of the oceans, but it is made of the same material as the continental crust.
Question 2
Which of the following statements about the cosmic background radiation is not true?
A) It has a temperature of about 3 degrees K above absolute zero.
B) It appears essentially the same in all directions (it is isotropic).
C) It had a much higher temperature in the past.
D) It is the result of a mixture of radiation from many independent sources, such as stars and galaxies that formed within the first billion years of the Big Bang.
E) It was discovered by Penzias and Wilson in the mid-1960s.
A soil surface crust that includes nitrogen-fixing, soil-enriching cyanobacteria.
lower digestive
A healthy diet is made up of well-balanced nutrients.
Distribution of Crust Remaining from Archean and Proterozoic
Synaptic Density
Chalk cliffs 90 meters (300 feet) high along the shore in Dover, England, were once seafloor