题干

△ABC中,∠A=30°,∠C=90°,作△ABC的外接圆.如图,若弧AB的长为12cm,那么弧AC的长是(   )

A:10cm

B:9cm

C:8cm

D:6cm

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C

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     The answer to protecting and saving marine(海洋) wildlife can start with cutting back on something Americans use every day—plastic drinking straws. Actor Adrien Grenier, best known for playing Vincent Chase in 2015 movie Entourage, has launched a campaign to reduce the amount of single-use plastic usage in this country in order to protect and save marine wildlife and the environment. Plastic drinking straws are among many single-use plastic products contributing to the shocking loss of marine life, but they’re a great place to start because they’re something Americans are using by the hundreds of millions without any awareness that they’re so damaging.

     According to Ecocycle, an international environmental organization, Americans use more than 500 million straws daily, which are enough to fill 127 school buses each day, and they can’t be recycled. They means plastic straws end up in landfills or oceans, where fish and other marine wildlife mistake the small bits for food and swallow them. After seeing a photo of a whale beached on the shore with a belly full of plastic, Grenier felt the inspiration to launch the Lonely Whale Foundation, hoping to inspire and educate others on the challenges facing marine life.

     Along with stopping the use of straws, Grenier hopes to educate consumers on the dangers of other single-use plastic items such as grocery bags and water bottles. While many Americans use these plastic products in their daily life, there are more sustainable alternatives that can help protect the environment. Ecocycle recommends the use of straws made from stainless steel, glass, and even bamboo instead of plastic. You can buy a number of these environmentally friendly straws online and in stores.

同类题4

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    Last weekend, I was blessed with an opportunity to serve as a volunteer in Maryland. I don't have a car and the closest Amtrak station is about 30 minutes away from the actual site so I wasn't sure1I would get there. I started thinking that maybe it wouldn't be2and after a really long week, I thought that maybe I shouldn't3at all. But I went ahead and posted a request for a4on the ride-share board.

    A few days later, an individual I had never met5that he would be able to pick me up and6me off at the station. He was also planning on serving but said he would wait7my train arrived before driving out there. How kind8this person whom I've never even met, I thought to myself. My heart9, and the stress I had been feeling from my week10away.

    When my new friend drove me to the train station, he11that it was in a deserted kind of area. There was no one12around. It was cold outside, and I still had 30 minutes to wait. So he13his car and said, “We will wait for the train to come together.”

    I couldn't believe his compassion and14. I knew that he had to be at work the next day15me, and that his wife and son were waiting for his return. But he just waited there with me so16, generously serving with his time.

    With five minutes17before the train arrived, he shared with me stories from his childhood. As a young boy, he18sit near the edge of the train tracks, excitedly waiting for the trains to rush by with all their force. That night, before returning home to his family, he waited with me as my train19. It didn't rush by at full force but I left that station20the full force of his compassion and generosity.