<span>The birthrate and the death rate were about equal.</span>
The force of gravity increases - when an objects mass increases.
Weight is - caused by gravity affecting mass.
Mass is - the amount of matter in an object.
The force of gravity decreases - when distance increases.
Answer:
<u>Geocentric Model</u>: - this model is Earth Centered
-Retrograde motion is explained by epicycles
<u>Heliocentric Model</u>: - This model is Sun Centered
-Retrograde motion is explained by the orbital speeds of planets
<u>Both models</u>:- Epicycles and deferents help explain planetary motion
-Planets move in circular orbits and with uniform motion
-The brightness of a planet increases when the planet is closest to Earth
Explanation:
Retrograde motion is an apparent change in the movement of the planet through the sky. Ptolemy's model of the solar systems was geocentric, where the Sun, Moon, planets and start all orbit the Earth in perfectly circular orbits. However this perfectly circular orbits around the Earth did not explain the occasional retrograde motion of the planets. In the Copernicus' heliocentric model, retrograde motion of planets is naturally explained. The explanation for retrograde motion in a heliocentric model is that retrograde occurs roughly when a faster moving planet catches up to and passes a slower moving planet.
The population density of Europe, as a whole, is 143 people per square mile. This makes Europe the second most densely populated continent in the world, with the first place being occupied bu Asia, so we can say that Europe is a densely populated continent as a whole.
It has to be taken in notice that Europe is a continent that has an aging population, the fertility rate is very low, and the life expectancy is high. Interestingly enough, even though there's only three countries in the whole continent that have a positive fertility rate, the population of the continent is still growing, slowly, by 0.3% annually, but it is growing. The growth is mainly because of the migrants, mainly from the Middle East and Africa, and apart from increasing the number of the population with their entry, they also tend to have a high fertility rate.
<span>Landslides refer to the process by which natural
forces move weathered rocks and soil from one place to another. This usually
occurs on a slope where the failure of materials results to the movement of
rock and soil. This debris is moved by the natural force of gravity which can
cause massive destructions in areas that are highly elevated. </span>
