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By about 2020 a new company from India will be opening dollar stores all over the world to sell their products. They will be a huge success, selling a lot of big things for low prices.
At these stores, they will sell a car that is customized(定做) to the customer's needs. So you will buy your car piece by piece. What's the point of buying a top if you don't need one? Why buy sides to your car if you want a good view? If you always drive alone, what's the point of buying four seats? The solution is to buy only what you need; pay a dollar for each wheel, a dollar for the engine, a dollar for the floor, a dollar for a seat, and away you go. When it looks like rain, run back and buy a roof.
When winter comes you can buy the sides and top; or fold up what you have and store it. Reliability(可靠性) won't be a problem because when something breaks down, just throw it away and buy a new one. When you get tired of the color of style, just replace it. While it may feel like you are always dishing out money, by the time you've done, you might only pay $12.00 for the entire car, so let's not complain.
This store will be such a big hit in India.
为植物必需的矿质元素的一般实验方法是（ ）