题干

如图为保温箱的简化电路图,A为温度传感器(不考虑其电阻),它的作用相当于开关,达到设定温度时自动断开电路;低于设定温度时,自动接通电路.S是保温箱的温度设定开关,它一共有三个挡,分别为60℃、50℃和40℃,加热功率分别为90W,72W和45W.电源电压为36V,R1、R2、R3都是发热体.则下面说法不正确的是(   )

A:当S拨至1位置时,功率为45W

B:当S拨至2位置时,功率为72W

C:当S拨至位置3时,电路中的电流是1.25A

D:R1的电阻为14.4Ω

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A

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    Not every parent looks forward to the day when their child goes off to school. In fact some parents are not sending their children to school at all. Instead they are choosing to teach their children at home. This is called homeschooling. Parents, caregivers, or private tutors educate children individually at home instead of sending them off to be formally educated in public or private schools. In the U.S. only about three percent of children are homeschooled.

    There are many reasons why some parents choose to homeschool. One reason is that some parents do not feel their children are safe in school because of bullying (恃强凌弱). It is said that bullying is very common in the school. Other parents want their children's education to be based on their religion or moral beliefs. Yet other parents think the education in school is not good enough. Homeschooling is also seen as a choice for families that live in rural areas, and families that move frequently.

    There are many different ways to homeschool, and homeschooling allows parents to design lessons based on their children's needs. Families can purchase textbooks to use or create their own materials. Some parents follow a philosophy called unschooling, which allows a child to determine when and how they want to learn based on their natural ability. Some worry that homeschooling means students won't have opportunities to communicate with others.

    To solve this problem, some families have created activities, where a group of homeschooled students will learn and play together and participate in activities that would normally happen in school like field trips.

    Besides, being homeschooled doesn't mean a student cannot go to college. Most colleges accept homeschooled students. And the homeschooled students can get the same degrees, too.

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