题干

按要求完成.
①在如图中描出下面各点,并依此连成一个三角形;A(2,7)、B(6,7)、C(4,9)
②画出三角形向下平移5格后的图形;
③将三角形缩小为原来的
1
2
,画在右边,要求点A画在A′上;
④画出正方形绕O点顺时针旋转180°后的图形,这时两个正方形组成了一个新图形,画出新图形的其中一条对称轴.
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解:根据题干分析,画图如下:

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    One of the newest words on the coffee stage is “shade grown coffee”. Shade grown coffee isn't new. In fact, until only a few years ago, shade grown coffee represented the major coffee beans sold on the world coffee market. The coffee plant is a natural shade lover, growing best in the shade afforded by an overgrowing canopy (树冠) of rain forest plants. That canopy protects the coffee plant from sunlight that reduces its production and kills it.

    Shade grown coffee is, however, more expensive to grow, at least in the short run. Growing coffee in the shade means that coffee growers also have to spend time working on the protectors. It means that less land is left to produce coffee beans. The arrival of technically engineered coffee plants that grow well in the sun represented a major development in coffee industry. Because there was no need to grow shade trees to protect the coffee trees, farmers could use more and more land to grow coffee trees, increasing their productivity and leading to more money for the coffee plantations (种植园) and farmers.

    However, it was not a good idea to move away from shade grown coffee. The sheltering canopy provided more than just shade for the coffee trees. Those plants provided shelter for birds and other animals who feed on pests.

    They help to fix nitrogen in the soil, and nitrogen is a natural fertilizer which makes plants grow more successfully. The increase in land used to grow sun loving coffee trees also had an unexpected effect on the law of supply and demand. The increased production resulted in a huge amount of coffee beans coming to the market, which brought down prices.

    Moreover, most experts agree that shade grown coffee is better in taste than coffee grown in full sun. Plants grown in shade take longer to develop. The slower growing time helps to improve the coffee's taste. You can buy a can of shade grown coffee to replace your usual sun coffee. One cup of coffee a day---it's a small price to pay for a better world.