Th correct answer is letter A. Echo sounding is very useful for depth profiles where SONAR is used to determine the depth of water through the transmission of sound pulses. It is calculated by checking the interval between the mission and the pulse that is recorded within the SONAR device.
, the five countries with the largest number of Catholics are, in decreasing order of population, Brazil<span>, </span>Mexico, thePhilippines<span>, </span>the United States<span>, and </span>Italy<span>.</span>
By observing how seismic waves are absorbed and refracted, scientist have been able to work out where the properties of the earth change dramatically. our understanding of the internal structures of the earth and the size of its core is based on these observations.
basically:
size of core
structure of the earth I.e. the layers of the earth
and I think the last one is how the internal structure is changing? not sure on the last one but its still a solid guess.
