Lava is rock that has undergone a physical change and has liquefied. What is known about this change?Lava is rock that has undergone a physical change and has liquefied. What is known about this change?

radioactive dating, also known as  radioisotope dating  is a process that in  estimating the approximate  age  of  rocks. these data can be analyzed from  the studies dealing with the  decay of the radioactive elements that are present in these rocks. in nature, there are a few types of materials or atoms which are quite unstable and they spontaneously decay or breakdown to form other kinds of atoms.

in the 1950s, country music came into its own before rock-n-roll took off in the 60s while jazz and classical music continued to innovate

the american colonists were happy with their vicorty, but the french were mad and the french and indians were not alies, and neither were the french and colonist. i think,

the correct answer is 50.