题干

请回答下列与水有关的问题.

(1)一壶水烧开了,壶盖被顶开,这是因为____ 

(2)硬水会给生产和生活带来许多不便,检验生活用水是否为硬水的物质是 ①____ ,生活中有些硬水可用 ②____ 的方法降低它的硬度;

(3)农业和园林浇灌植物时,将大水漫灌改为喷灌、滴灌的目的是____ 

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水分子间隔变大,肥皂水,煮沸,节约水资源

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    Developing healthy eating habits starts from childhood, therefore it is important for parents to teach and provide children with a healthy diet. DPHSS administrator of the Bureau of Nutrition Services, Charlie Morris told KUAM News, “A healthy diet for a child consists of a lot of fruits and vegetables in the diet limiting the amount of simple sugars in the diet and high fat food and highly processed food.”

    This means staying away as much as possible from food such as chips, cookies, candies and sugary drinks, as all children need to have meals which involve a well-balanced diet. Community nutritionist Thelma Romoso said, “The fruit, the vegetable, the grain, the protein, and also the milk, the diary product, so for the fruits it's easy for a mother to go into the two plus three concept of fruits and vegetables or five a day.”

    This concept means that there are at least two servings of fruits a day, three servings of vegetables a day which can be served for lunch and dinner. As for protein parents can make a variety of dishes from chicken, beef, fish or even dried beans to pledge the child gets three servings a day.

    Morris said that the child's hunger level controls how much is eaten and the parent controls what and when the meal is offered, saying, “Mom needs to ensure that the food offered is good food for the child to eat and throughout the day depending on how active they are, snacks are not a bad thing, so the mom should offer good kinds of snacks.”

    When it comes to preparing your child's lunch and snacks for school, make sure to keep in mind that the food you provide should not only be a source of energy but also be nutritionally beneficial such as fresh fruits, and whole grain bread. But parents must be sure to remember that a good nutritional diet must be balanced with physical activity, namely it is important that children get outside and run around and play and get activity in addition to eating a good diet.