This passage discusses various topics in a children's educational context. It covers why the sea is salty due to the accumulation of minerals, how trees lose their leaves in autumn to conserve energy, the science behind yawning, why we see rainbows, why we can't see in the dark without light, and the causes of hiccups. The passage uses simple explanations and examples to make these concepts understandable to children.
Sure, here are the key facts extracted from the provided text without opinions:
1. Rainwater washes salt and minerals out of rocks when flowing over land.
2. These minerals are carried by rivers and streams into the sea.
3. Salt remains in the sea as water evaporates, making seawater salty.
4. Approximately 96% of Earth's water is in the oceans.
5. Trees lose their leaves in the autumn due to shorter days and reduced sunlight.
6. Evergreen trees retain their leaves throughout the year.
7. Yawning is an involuntary action related to tiredness, stress, and boredom.
8. Yawning involves inhaling a large amount of air and expanding the chest.
9. The moon appears to shine because it reflects sunlight.
10. Rainbows form when sunlight passes through raindrops and is refracted.
11. Raindrops act like prisms, splitting sunlight into its seven colors.
12. Darkness is the absence of light, making objects invisible.
13. Torchlight or other sources of light help us see in the dark.
14. Hiccups occur when the diaphragm becomes irritated and contracts suddenly.
15. Holding one's breath is a common remedy for curing hiccups.
Please note that these facts are presented in the order they appear in the text.