根据短文理解，选择正确答案。

    People who smoke could lose around one third of their everyday memory, researchers say.

    A study by a team at the University of Northumbria has shown that smokers lose more of their memory when compared to non-smokers. And the research also found that those who kicked the habit saw their ability to recollect information restored to almost the same level as non-smokers.

    The study involved more than seventy 18-to 25-year-old volunteers and included a tour of the university's campus. Those who took part were asked to recall(回忆；回想)small details, such as music acts listed to play at the students' union and tasks completed at various points---known as a real-world memory test.

    Smokers performed badly, remembering just 59 percent of tasks. But those who had given up smoking remembered 74 percent and those who had never smoked recalled 81 percent of tasks.

    Dr. Tom Heffernan, who leads Northumbria University's Collaboration for Drug and Alcohol Research Group, said the findings would be useful in anti-smoking campaigns. He said, “Given that there are up to 10 million smokers in the UK and as many as 45 million in America, it's important to understand the effects that smoking has on everyday cognitive function.”

    This is the first time that a study has set out to examine whether giving up smoking has an effect on memory. We already know that giving up smoking has huge health benefits to the body, but this study also shows how stopping smoking can bring a series of benefits to cognitive function. The research will now investigate the effects of second-hand smoking on memory, while Dr. Heffernan will look into third-hand smoking, such as toxins (毒素) left on curtains and furniture.

看拼音，写汉字。

晚shàng ____，爸爸在台灯xià____看书。

果盘里有sān gè____苹果。

如果$\frac{x}{y}=3$，则$\frac{x+y}{y}$等于(     )

请简要说出检验物体是否带电的三种方法？

按照板块构造学说的观点，结合如图判断，下列说法正确的是（  ）