题干

在4Al+3O22Al2O3中,____ 份质量的铝和____ 份质量的氧气反应,生成____ 份质量的三氧化二铝.各物质质量比为____  .

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108,96,204,9:8:17

同类题1

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                                                                                  She Walked Through Fire

    On Thanksgiving weekend, the Heffelmire family gathered for a meal at their home. After dinner, the family went down to the finished basement to relax except Charlotte's father, Eric, who was in the garage to fix his truck.

    Around 8 p.m., Charlotte decided to check on her dad. She walked through the kitchen. When she opened the side door to the garage, black smoke rose up into the kitchen. She could barely make out her father lying on his back, trapped under the truck. He'd removed the front passenger-side tyre and raised the truck on a jack(千斤顶). The truck had slipped off the jack, and now the whole weight of the wheel was on his chest and shoulders.

    Charlotte ran to the front of the truck and struggled to lift it. Eric was still conscious, and he yelled, “You got it! One more try!” She tried again and was able to tip the truck backward just enough for her to pull her dad by the shirt with both hands from under the truck.

    She dragged him across the garage and 20 feet down the driveway. Then she ran back to the garage, which had burst into flames. “I was afraid the car was going to explode,” says Charlotte, so she climbed into the truck, which faced forward, turned the key, and pressed the gas pedal(油门). The car slowly rolled out, the metal wheel scratching loudly against the concrete.

    Safely on the driveway, Charlotte stopped the truck and ran back to the basement. “There's a fire! Everybody get out!” she yelled as she picked up her three-month-old niece and ran out. Outside, she handed the baby to her mom, and then ran around to the burning garage. She picked up a garden hose(水管)and sprayed the fire while calling 911.

    A few minutes later, firefighters and an ambulance arrived. Charlotte was treated for second-degree burns on both her feet and face. Her dad had injuries on his chest and shoulders, as well as minor burns on his face. The garage and the house were damaged but the family survived.

    The Heffelmires are staying in an apartment while their house is rebuilt. “Charlotte is a remarkable kid,” says her dad. Charlotte, however, simply says, “ I was saving my family and my house. I wasn't going to let my dad die.”

同类题2

    Never go into a supermarket hungry! This is a good piece of advice. If you go shopping for food before lunchtime, you'll probably buy more than you plan to. Unfortunately, however, just this advice isn't enough for shoppers these days. Modern shoppers need an education in how and how not to buy things at the store. First, you check the weekly newspaper ads. Find out the items that are on sale and decide if you really need these things. In other words, don't buy anything just because it's cheaper than usual! Second, never let "New and Improved!" or "All Natural”on the front of a package influence you. Instead, read the list of contents on the back. Third,compare prices: that is, you should examine the prices of both different brands(品牌)and different sizes of the same brand.
    Another suggestion for shoppers is to buy ordinary items instead of famous brands. Ordinary items in supermarkets come in plain packages. These products are cheaper because producers don't spend much money on packing or advertising. However, they are still of high quality. In the same way, in buying clothes, you can often find high quality and low prices in brands that are not famous. Shopping in discount clothing stores can help you save a lot of money. Although these stores aren't very attractive, and they usually do not have individual dressing rooms, not only are the prices low, but you can often find the same famous brands that you find in high-priced department stores.
    Wise shoppers read magazine ads and watch TV commercials(商业广告),but they do this with one advantage: knowledge of the psychology behind the ads. In other words, will-informed shoppers watch for information and check for misinformation. They ask themselves questions: Is the advertiser hiding something in small print at the bottom of the page? Is there any real information in the commercial, or is the advertiser simply showing an attractive image? With the answers to these questions, shoppers can make a wise choice.