The viscosity of magma is determined by its silica content.
Basalt magma, on the one hand, which is often
of low viscosity, has a low silica content of approximately 50% or less. Rhyolite magma, on the other hand, has high viscosity due to the high silica content of
approximately 70% and more.
Gas content and temperatures of the magma are the other factors
that determine an explosive or
nonexplosive eruption. High temperatures
and high gas content (coupled with high viscosity)
cause violent explosions.
The total amount of water in the planet
Answer:
r u on edg
Explanation: if its edg i know it
Answer:
dang alot of work have a great day
<span>The correct answer, according to Lamarck's theory of evolution, is that A) "Land mammals progressively modified their organs to survive in water. These features were passed on to the next generation, and the mammal gradually evolved into today's aquatic mammals."
Lamarck believed that animals could (a) acquire the traits that they needed and (b) pass those acquired traits on to their offspring. According to part (a) of Lamarck's idea, if I needed to be a faster swimmer (if I were an athlete), I could modify my body to have webbing between my toes, which would allow me to beat the competition! Also, according to part (b) of Lamarck's idea, if I were a body builder and developed (acquired) very large muscles through my training, then my children should be born with very large muscles. Based on the these examples, you can see why Lamarck's theory of evolution is not the one that is generally accepted by scientists. Rather, Darwin's theory of evolution, in which the traits that we are born with confer either an advantage or disadvantage to us in our particular environment, which determine whether or not we are successful (ie, survive and reproduce). New traits come about randomly by mutation, not by our need for them.</span>
