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People know the dangers of fires. It’s good for a family to learn how to prepare for a fire. Everyone in the family should know the following fire rules:
★ Don’t open a hot door! The fire can grow more quickly if you open the door.
★ Stay close to the floor! 1. Smoke can be more dangerous than fire. The best air is near the floor because smoke rises.
★ What will you do if your hair or clothes start to burn? First, stop! Don’t run! The fire burns faster because of more air. Drop! Fall to the floor. Then roll! Turning over and over will make the fire go out. Put a blanket (毯子) around you to keep air away from the fire that may still be on you.There are many possible reasons for fires. A wise family is ready all the time. 2. If there is a fire, don’t forget to call 119 for help.
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同类型试题
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
