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Do you always find it is raining when you walk out? Or are you always buying umbrellas and leaving them home when it rains? There is a new umbrella that could solve both problems.
The umbrella will not only tell you the weather, but also let you know you’ve left it behind. How does it work? The umbrella will send a message to your smartphone. And it says “Hey, it’s going to rain in 15 minutes where you are, so you’d better take your umbrella.”
Besides, if you are forgetful, you may never leave an umbrella on a bus or somewhere else again. The umbrella will send a warning to your smartphone if you leave it behind. The new umbrella is expected to go on sale soon. Though it is a good idea and it looks pretty cool, the umbrella will cost you $185. Maybe you will just check the free weather apps (应用程序) on your smartphone and take an umbrella with you when it is going to rain.
1．How many problems can the new umbrella solve?2．What else can the new umbrella tell you besides the weather?
3．Where will the new umbrella send a warning?
4．When will the new umbrella be sold?
5．Does the writer think the new umbrella looks cool?
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
