FIRST NAME _________________________ INITIAL ______
Put a circle around the number next to each correct answer.
I. At any ocean beach you can see the water rise up toward high tide. Something is pulling the water up. We now know that the moon is doing the pulling. How can it pull? We call the pull gravitation. All matter everywhere pulls all other matter everywhere. The bigger the object, the greater the pull. The moon is big enough to pull the earth, and it pulls the water on the earth. The moon pulls the water facing the moon. When you see high tide, you know that the moon is pulling the water up.
A. When you drop something, and it falls to the ground, it falls because of -
1. the moon.
3. its size.
4. the sun.
B. High tide is caused by -
2. all matter everywhere.
3. the earth.
4. the water.
C. The moon pulls -
1. all matter.
2. water only.
3. the earth only.
4. the tides.
D. If the earth did not spin, -
1. there would be no tides.
2. the moon would not pull the water.
3. the earth would not pull the moon.
4. there would be no gravitation.
II. The sun also pulls the earth. However, the sun is much farther away from the earth than the moon, and so the pull, that is, the gravitation, is less. Sometimes, the sun and the moon pull together on the same side of the earth. Then, the high tide is very high, indeed.
A. The pull of the sun on the earth is called -
2. high tide.
4. pulling together.
B. When there is a very high tide, the sun and the moon are -
1. on opposite sides of the earth.
2. on the same side of the earth.
3. near to each other.
4. farther away than at other times.
C. The sun pulls the earth less than the moon because -
1. it is so large.
2. it is farther away than the moon.
3. the sun and the moon have no water.
4. it is on the opposite side of the earth from the moon.
D. At low tide, -
1. the water is piling up somewhere else.
2. the sun is much farther away.
3. the sun and the moon are not pulling together.
4. the sun and the moon are on the same side of the earth.
III. Why does oil not mix well with water? We know that water mixes well with water. If you add hot water to cold water, you soon have lukewarm water. Alcohol, too, mixes well with water. Alcohol and water are quite similar. Water is composed of oxygen and hydrogen, whereas alcohol is composed of oxygen, hydrogen, and carbon. Why do oil and water not mix well? The reason is that they are not similar. The molecules of water, that is, the tiny pieces of water that include oxygen and hydrogen, are very small, whereas the molecules of oil are, by comparison, enormous and very different in their composition.
A. Water molecules include -
1. oxygen and hydrogen.
2. oxygen, hydrogen, and carbon.
3. tiny pieces of water.
4. both hot and cold molecules.
B. The molecules of alcohol -
1. are enormous.
2. are similar to oil.
3. mix well with water.
4. contain only oxygen and hydrogen.
C. Oil and water do not mix well because -
1. they are similar in composition.
2. water has big molecules.
3. they are both composed of oxygen and hydrogen.
4. their molecules are very different.
D. A molecule of water is -
1. bigger than a molecule of oil
2. composed of oxygen, hydrogen, and carbon.
3. similar to a molecule of oil.
4. a very small piece of water.
IV. From where does a flower get its smell? It gets its smell from an oil that the plant produces. The oil is volatile. Long ago, volatile meant flying. The oil seems to be flying, for it escapes into the air. Insects that smell the oil fly to the flower, where they leave behind them the pollen that the flower needs to grow seeds. Some plants do not need insects to bring pollen. They depend on the wind to bring it. These plants usually have little smell or no smell at all.
A. Something that is volatile -
1. is carried on wings.
2. leaves pollen.
3. is necessary for seed growth.
4. escapes into the air.
B. This story is mainly about -
1. the smell of flowers.
2. insects that fly to flowers.
3. how flowers get pollen.
4. volatile oils.
C. Flowers with little smell or no smell at all -
1. need insects to bring pollen to them.
2. depend on volatile oils.
3. depend on the wind to bring pollen to them.
4. do not need pollen.
D. Insects in the story are attracted to a flower by -
3. volatile oil.
4. the beauty of the flower.
V. There are several birds, once common, that have died out in the last few hundred years, so that now not one of them exists. The dodo was quite common on the island of Mauritius 300 years ago, but there is not one alive today. It was easy prey to animals new to the island, because it could not fly on its small wings. In New Zealand there used to be birds called moas, which were twice as high as the biggest man. They have all died out. The great auk, which used to come in thousands to the shores of Newfoundland, is another bird that has died out in the last few hundred years.
A. This story is mainly about -
1. animals that have died out.
2. birds that have died out.
3. why birds have died out.
4. where birds that have died out lived.
B. The dodo died out because -
1. of its size.
2. it was new to the island of Mauritius.
3. it was common on the island of Mauritius.
4. it was easy prey to animals new to the island.
C. The great auk was -
1. a bird.
2. a kind of dodo.
3. a kind of moa.
4. a bird with small wings.
D. Moas were -
1. about two feet tall.
2. about five feet tall.
3. about twelve or fourteen feet tall.
4. about twenty feet tall.