题干

如图表示酶的有关实验:取甲、乙两支洁净的试管分别注入3 mL淀粉糊。然后在甲试管中注入2 mL新鲜的小麦淀粉酶滤液,在乙试管中注入2 mL清水,振荡这两支试管。下列说法正确的是  
     

A:往两支试管中分别滴入1滴碘液,在35℃水浴中保温 5 min,乙试管变蓝

B:两支试管内各物质的量要求相同,是为了排除物质用量的不同对实验结果的影响

C:35℃是小麦淀粉酶起催化作用的最适温度

D:若用该装置来验证酶的专一性,可以用斐林试剂检验颜色变化

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B

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    Natalie Doan, 14, has always felt lucky to live in Rockaway, New York. Living just a few blocks from the beach, Natalie can see the ocean and hear the wave from her house. "It's the ocean that makes Rockaway so special," she says.
    On October 29, 2012, that ocean turned fierce. That night, Hurricane Sandy attacked the East Coast, and Rockaway was hit especially hard. Fortunately, Natalie's family escaped to Brooklyn shortly before the city's bridge closed.
    When they returned to Rockaway the next day, they found their neighborhood in ruins. Many of Natalie's friends had lost their homes and were living far away. All around her, people were suffering, especially the elderly. Natalie's school was so damaged that she had to temporarily attend a school in Brooklyn.
    In the following few days, the men and women helping Rockaway recover inspired Natalie. Volunteers came with carloads of donated clothing and toys. Neighbors devoted their spare time to helping others rebuild. Teenagers climbed dozens of flights of stairs to deliver water and food to elderly people trapped in powerless high-rise buildings.
    "My mom tells me that I can't control what happens to me," Natalie says. "But I can always choose how I deal with it."
    Natalie's choice was to help. She created a website page matching survivors in need with donors who wanted to help. Natalie posted introduction about a boy named Patrick, who lost his baseball card collecting when his house burned down. Within days, Patrick's collection was replaced. In the coming months, her website page helped lots of kids: Christopher, who received a new basketball; Charlie, who got a new keyboard.Natalie also worked with other organizations to bring much-need supplies to Rockaway. Her efforts made her a famous person. Last April, she was invited to the White House and honored as a Hurricane Sandy Champion of Change.
    Today, the scars of destruction are still seen in Rockaway, but hope is in the air. The streets are clear, and many homes have been rebuilt. "I can't imagine living anywhere but Rockaway," Natalie declares. "My neighborhood will be back, even stronger than before."