题干

小明使用10×目镜和16×物镜的显微镜观察到如下物像,若要看到完整的物像,可采取下列哪种办法(  )

A:把目镜换成5×,同时把物镜换成40×

B:把目镜换成5×,同时把物镜换成16×

C:把物镜换成40×,目镜16×

D:把目镜换成16×,物镜16×

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B

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    Peter, a high school student, was pretty busy with school, and he was on the soccer team. High school was hard, because everyone wanted to have nice clothes, hang out, drive cars, and all these cost money. Peter's father was the sort of guy that believed you had to earn whatever you got, so he wasn't just about to hand over lots of money for Peter to use to have fun. So, he had to get a job.

    During his freshman year summer vacation, his classmate got him a job working on a hay(干草)farm. He threw hay up into wagons as the tractor drove around fields, and then they stacked(剁起)it in the hot barn. It was a hot, low-paying job.

    He once worked a few nights a week at a grocery store. He put things on the shelf. It was a lot of lifting and carrying, and his arms were strong from this and the previous job. It was dull and didn't pay much.

    He took some time off when soccer got serious, but the following summer he tried working at a lumber yard. It was hot outside, but he got a lot of exercise lifting and carrying things like boards and drywall. He also learned a lot about building supplies. It still didn't pay well.

    From there, he spent a year doing some tutoring for a friend of the family, but that was Piecemeal. His first real job came the last year at school, when he fixed registers and worked on computers at a big box store. It was his favorite job yet, but it still didn't pay well.

    What Peter realized with all of these jobs was that he needed a better-paying job! The only way to get that was to get trained or educated He could go to school and get a 2-year degree in an office or technical position. His other choices were going to a 4-year college or joining the army. He wasn't sure what he was going to do yet, but he knew he had to do something. Jobs were a lot of work, money was hard to earn, but he liked staying busy and being able to buy things. Peter wanted the most out of life, and that meant education.