FIRST NAME _______________________ INITIAL ______

Put a circle around the number next to each correct answer.

I. The White Cliffs of Dover on the coast of England are chalk. Chalk is composed of the shells of sea animals. How, then, did they come to make up huge cliffs on the seacoast? Well, at one time, the chalk was under the ocean. As the animals with shells died, the shells fell to the ocean floor and piled up over millions of years, often to great thicknesses. Then, the ocean floor rose, and the water fell back, leaving the chalk to make up dry land. In many parts of England and France you can scratch the soil and find chalk underneath. Some train tunnels go through chalk.

A. This story is mainly about -

1. the natural history of chalk.

2. sea animals with shells.

3. the seacoast of England.

4. the many places where chalk is found.

B. When they die, some sea animals leave behind -

1. sea coast.

2. ocean floor.

3. shells.

4. white cliffs.

C. The White Cliffs of Dover formed because -

1. sea animals died.

2. there was chalk on the ocean floor.

3. the ocean floor rose up.

4. there is chalk under the soil.

D. Some train tunnels -

1. leave the water behind.

2. allow the train to go through chalk.

3. are on the seacoast of England and France.

4. are stopped by the shells of sea animals

II. We know that gold and silver are elements. An element consists of atoms of only one kind, unlike water, which consists of both hydrogen and oxygen. Another element is radium. Radium is especially interesting, because it produces heat. When soil is carried by rivers down to the sea and falls to the bottom, it often carries radium in it. As more and more soil is washed down into the ocean, more and more radium is carried in it. There, as elsewhere, it constantly produces heat.

A. This story is mainly about -

1. a heat-producing element.

2. gold and silver.

3. soil that is washed down into oceans.

4. atoms of only one kind.

B. Oxygen and hydrogen -

1. are not in the same class as silver and gold.

2. are unlike water.

3. are elements.

4. are not elements.

C. Some heat on the ocean floor comes from -

1. oxygen and hydrogen.

2. radium.

3. the water from rivers.

4. gold and silver.

D. One heat-producing element is -

1. gold.

2. silver.

3. radium.

4. hydrogen.

III. An iron or steel bridge swells (gets larger) when warmed by the sun and shrinks (gets smaller) when it becomes colder. Heat makes everything expand, and cold makes everything contract. Cold is the absence of heat. Metals change their size when heated or cooled, and this change is noticeable in a bridge that is made of iron or steel. The builder of a bridge must leave empty spaces for the metal to expand into. Have you noticed that concrete sidewalks have cracks every few feet? These cracks provide space for the concrete to expand into when heated.

A. This story is mainly about -

1. the effect of heat on everything.

2. metal bridges.

3. the cracks in sidewalks.

4. the absence of heat.

B. Another word for "swells" is -

1. warms.

2. shrinks.

3. contracts.

4. expands.

C. Empty spaces allow room for a material to -

1. warm.

2. shrink.

3. contract.

4. expand.

D. The sun causes materials to -

1. expand.

2. shrink.

3. contract.

4. cool.

IV. An ear of corn on a corn plant is protected by a husk, and at the end of the ear, emerging from the husk, you can see a bunch of silk-like threads. What is the purpose of these threads? Well, each thread is attached to a kernel of corn inside the husk, and each kernel of corn, if it is fertilized by pollen, can become a seed that can grow into a new corn plant. How does pollen reach the kernel? It travels through the silk-like thread, which is a hollow tube.

A. This story is mainly about -

1. threads.

2. new corn plants.

3. the purpose of corn's silk-like threads.

4. kernels of corn.

B. The part of corn that we eat is -

1. silk-like threads.

2. kernels.

3. new corn plants.

4. husks.

C. Pollen makes it possible for kernels to become -

1. silk-like threads.

2. seeds.

3. husks.

4. a hollow tube.

D. Pollen travels in -

1. a kernel.

2. the ear of corn.

3. a hollow tube.

4. the covering of the ear.

V. Why is it impossible to sink in the Dead Sea? The reason is that, not only is the water in the Dead Sea heavier than ocean water and much heavier than fresh water, but it is also heavier than a person's body, when equal parts are measured. You can't sink in something that is heavier than you are. The reason for the heaviness is extreme saltiness. Are there materials that would sink in the Dead Sea? Yes, and I'll bet that you can think of some.

A. This story is mainly about -

1. why you can't sink in the Dead Sea.

2. the saltiness of water.

3. the reason for the saltiness of the Dead Sea.

4. how heavy your body is.

B. Water in the Dead Sea is heavier than -

1. a person's body only.

2. ocean water, fresh water, and a person's body.

3. ocean water and fresh water only.

4. ocean water only.

C. The reason for the heaviness of Dead Sea water is -

1. ocean water.

2. materials that would sink.

3. salt.

4. fresh water.

D. "Equal parts" means -

1. a quart of one measured against a quart of another, for example.

2. Dead Sea water measured against ocean water.

3. ocean water measured against fresh water.

4. a person measured against fresh water.