Give reasons unit three for prep one:
1- the stars seem as light points although they are huge.
Because they are far from us.
*2. Astronomers do not measure the distances between stars by kilometers.
Because these distances is very large.
3. The inner planets are called small planets.
Because they are small bodies.
4. Mercury, Venus, Earth and Mars are called the inner planets.
Because they are near to the Sun.
5. Jupiter, Saturn, Uranus and Neptune are called the outer planets.
Because they are far from the Sun.
6. The outer planets are called giant planets.
Because they are very big.
*7-The densities of outer planets are low.
Because they consist of gaseous material.
8. Scientists explained the presence of hydrogen gas in
a solidified state on the surface of outer planets
Due to the high pressure and the coldness on their surfaces.
*9- The gravity on Earth’s surface is larger than that on Mars surface.
Because the mass of the Earth is larger than the mass of Mars planet.
10- Falling the apple from the tree on the ground.
Due to the Earth’s gravity.
11- Sometimes, we see some luminous lines in the sky
at clear nights.
Because of the burning of small rocky called meteors when they penetrate the Earth’s atmosphere
12- No one can see Halley’s comet more than two times in his life.
Because it takes the same position every 76 years
14- The tropical radius increases more than the polar radius.
Because the Earth is flattened at its poles and indented outward at the equator.
15-Concerning the volume, the Earth occupies the fourth position.
Because it is the biggest inner planet.
*16- The presence of white colour surrounds the planet Earth.
Due to the presence of the atmosphere that surrounds the Earth
*17- Some rock masses that fall from the space do not reach the Earth’s surface.
Because millions of small falling meteors completely burn before reaching the Earth’s surface.
18- The importance of ozone layer.
To protect living organisms from the ultraviolet radiations.
* 19 - Temperature on Earth’s surface suits the life of living organisms.
Due to the position of the Earth in the third order far from
the Sun
20- Steadfastness of the hydrosphere on the Earth’s surface.
Due to the gravitational force of the Earth.
21- Planet Earth is suitable for life.
Due to :The presence of hydrosphere.
— The presence of the atmospheric envelope containing oxygen gas which is needed for life.
— Its temperature is suitable during both day and night.
— Its atmospheric pressure are suitable.
*22- Earth’s inner core is rich in iron and nickel.
Because the inner part of the Earth was melted due to the high temperature that caused falling down of heavy elements such as iron and nickel towards the centre of the Earth.
23- The plant roots extend easily through the upper part of Earth’s crust.
Because the upper part is fragmented and loose.
24- The trees roots can’t extend easily through the lower part of Earth’s crust.
Because the lower part consists of different types of rocks.
*25. The crystals of minerals that form the plutonic igneous rock are large-sized.
Because magma at depth gets cool slowly, therefore minerals take a longer time to crystallize so, their crystals are large-sized.
26-. The crystals of minerals that form the volcanic rock are small-sized.
. Because the minerals that form it do not take the time required for crystallization, where lava cools quickly on the surface, therefore their crystals become small-sized.
*27. Th Volcanic rocks contain small circular holes.
Due to the extruding of gases from volcanic flows during their cooling and formation of rock.
28-. Granite has a coarse texture, while basalt has a smooth texture.
Because granite is a plutonic rock, while basalt is a volcanic rock.
*29-. The components of basalt rock are not seen by the naked eye.
Because it is a volcanic rock which has very small crystals.
30-. Limestone consists of mineral calcite.
Due to the precipitation of calcium carbonate in lime solutions.
*31- Effervescence takes place when hydrochloric acid is added to a sample of limestone
32-. Due to evolving of carbon dioxide gas.
32-. Some kinds of marble have colours.
Due to the presence of impurities.
41-Neweba and Dahab were the most damaged areas in Sinai Peninsula by earthquakes.
Because they were very close to the earthquake centre.
*42- Earth shaking takes place at the occurrence of earthquakes.
Due to release of energy in the form of different waves which spread through the crust as seismic waves causing the earthquakes.
43-. The eruption of volcanoes may be accompanied by shaking of ground.
Due to the movement of molten materials and trapped gases before and during their coming out of the surface.
33- During the occurrence of earthquakes, the metallic weight of seismograph remains steady.
Because the spring absorbs the shaking.
34-. Earthquakes may destroy and submerge some coastal cities.
Due to the formation of tsunami waves.
35. We cannot feel some earthquakes which are recorded by seismograph.
Because they are too weak to be felt by people.
*36-. After the occurrence of earthquakes, we must go to gardens, playgrounds, and places far from destroyed buildings.
To avoid hurting by collapsing buildings.
37- After occurrence of earthquakes and before your going out of a building, you mu cut out the electricity, gas and water.
To avoid fires or breaking water pipes.
38- Occurrence of volcano.
Due to the presence of weak part in the Earth’s crust, where the molten magma that contains gases under high pressure is extruded from the Earth’s surface.
*39- The rushing of the molten material at high speed during its going out of the vent
Due to gas pressure.
*40- Volcanic ash covers areas far away from the volcano.
As a result of volcanic eruption and spread of volcanic ashes by high pressures and wind motion.
41- The pipe of the volcano is called the neck of the volcano.
Because it lies directly under the vent (volcano opening)
.
42-. In some countries, volcanoes are considered as a source of energy.
Because it has a thermal energy that can be used in many things like generating electricity
43-. The soil that is formed from the volcanic projectile and ashes produces the most important crops.
Because it is rich in different elements.
44- We must take the wind direction in our consideration during the occurrence of volcanoes.
To avoid the poisonous gases emanated from the volcanoes
.
45- Neighbouring areas to volcanoes must be evacuated from people.
To protect them from poisonous gases and volcanic dusts. [left]
1- the stars seem as light points although they are huge.
Because they are far from us.
*2. Astronomers do not measure the distances between stars by kilometers.
Because these distances is very large.
3. The inner planets are called small planets.
Because they are small bodies.
4. Mercury, Venus, Earth and Mars are called the inner planets.
Because they are near to the Sun.
5. Jupiter, Saturn, Uranus and Neptune are called the outer planets.
Because they are far from the Sun.
6. The outer planets are called giant planets.
Because they are very big.
*7-The densities of outer planets are low.
Because they consist of gaseous material.
8. Scientists explained the presence of hydrogen gas in
a solidified state on the surface of outer planets
Due to the high pressure and the coldness on their surfaces.
*9- The gravity on Earth’s surface is larger than that on Mars surface.
Because the mass of the Earth is larger than the mass of Mars planet.
10- Falling the apple from the tree on the ground.
Due to the Earth’s gravity.
11- Sometimes, we see some luminous lines in the sky
at clear nights.
Because of the burning of small rocky called meteors when they penetrate the Earth’s atmosphere
12- No one can see Halley’s comet more than two times in his life.
Because it takes the same position every 76 years
14- The tropical radius increases more than the polar radius.
Because the Earth is flattened at its poles and indented outward at the equator.
15-Concerning the volume, the Earth occupies the fourth position.
Because it is the biggest inner planet.
*16- The presence of white colour surrounds the planet Earth.
Due to the presence of the atmosphere that surrounds the Earth
*17- Some rock masses that fall from the space do not reach the Earth’s surface.
Because millions of small falling meteors completely burn before reaching the Earth’s surface.
18- The importance of ozone layer.
To protect living organisms from the ultraviolet radiations.
* 19 - Temperature on Earth’s surface suits the life of living organisms.
Due to the position of the Earth in the third order far from
the Sun
20- Steadfastness of the hydrosphere on the Earth’s surface.
Due to the gravitational force of the Earth.
21- Planet Earth is suitable for life.
Due to :The presence of hydrosphere.
— The presence of the atmospheric envelope containing oxygen gas which is needed for life.
— Its temperature is suitable during both day and night.
— Its atmospheric pressure are suitable.
*22- Earth’s inner core is rich in iron and nickel.
Because the inner part of the Earth was melted due to the high temperature that caused falling down of heavy elements such as iron and nickel towards the centre of the Earth.
23- The plant roots extend easily through the upper part of Earth’s crust.
Because the upper part is fragmented and loose.
24- The trees roots can’t extend easily through the lower part of Earth’s crust.
Because the lower part consists of different types of rocks.
*25. The crystals of minerals that form the plutonic igneous rock are large-sized.
Because magma at depth gets cool slowly, therefore minerals take a longer time to crystallize so, their crystals are large-sized.
26-. The crystals of minerals that form the volcanic rock are small-sized.
. Because the minerals that form it do not take the time required for crystallization, where lava cools quickly on the surface, therefore their crystals become small-sized.
*27. Th Volcanic rocks contain small circular holes.
Due to the extruding of gases from volcanic flows during their cooling and formation of rock.
28-. Granite has a coarse texture, while basalt has a smooth texture.
Because granite is a plutonic rock, while basalt is a volcanic rock.
*29-. The components of basalt rock are not seen by the naked eye.
Because it is a volcanic rock which has very small crystals.
30-. Limestone consists of mineral calcite.
Due to the precipitation of calcium carbonate in lime solutions.
*31- Effervescence takes place when hydrochloric acid is added to a sample of limestone
32-. Due to evolving of carbon dioxide gas.
32-. Some kinds of marble have colours.
Due to the presence of impurities.
41-Neweba and Dahab were the most damaged areas in Sinai Peninsula by earthquakes.
Because they were very close to the earthquake centre.
*42- Earth shaking takes place at the occurrence of earthquakes.
Due to release of energy in the form of different waves which spread through the crust as seismic waves causing the earthquakes.
43-. The eruption of volcanoes may be accompanied by shaking of ground.
Due to the movement of molten materials and trapped gases before and during their coming out of the surface.
33- During the occurrence of earthquakes, the metallic weight of seismograph remains steady.
Because the spring absorbs the shaking.
34-. Earthquakes may destroy and submerge some coastal cities.
Due to the formation of tsunami waves.
35. We cannot feel some earthquakes which are recorded by seismograph.
Because they are too weak to be felt by people.
*36-. After the occurrence of earthquakes, we must go to gardens, playgrounds, and places far from destroyed buildings.
To avoid hurting by collapsing buildings.
37- After occurrence of earthquakes and before your going out of a building, you mu cut out the electricity, gas and water.
To avoid fires or breaking water pipes.
38- Occurrence of volcano.
Due to the presence of weak part in the Earth’s crust, where the molten magma that contains gases under high pressure is extruded from the Earth’s surface.
*39- The rushing of the molten material at high speed during its going out of the vent
Due to gas pressure.
*40- Volcanic ash covers areas far away from the volcano.
As a result of volcanic eruption and spread of volcanic ashes by high pressures and wind motion.
41- The pipe of the volcano is called the neck of the volcano.
Because it lies directly under the vent (volcano opening)
.
42-. In some countries, volcanoes are considered as a source of energy.
Because it has a thermal energy that can be used in many things like generating electricity
43-. The soil that is formed from the volcanic projectile and ashes produces the most important crops.
Because it is rich in different elements.
44- We must take the wind direction in our consideration during the occurrence of volcanoes.
To avoid the poisonous gases emanated from the volcanoes
.
45- Neighbouring areas to volcanoes must be evacuated from people.
To protect them from poisonous gases and volcanic dusts. [left]
