Why are urban populations easy to get diseases from food, according to the last paragraph?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35.

The increase in urbanization causes different problems. Air and water pollution are amongst the major issue we have to tackle.

In the first place, cars, factories and burning waste emit dangerous gases that change the air quality in our cities and pose threats to our health. Dangerous gases such as carbon dioxide and nitrogen oxides cause respiratory diseases, for instant, bronchitis and asthma. Those are also proved to have long-term effects on the environment.

Furthermore, with the increased population, it becomes difficult to manage the waste generated in cities. Most of the waste is discharged or dumped into rivers or onto streets. The waste pollutes water and makes it unfit for human consumption. Subsequently, it becomes more and more difficult for city dwellers to get clean water. Some cities in Africa are unable to provide adequate water supply because most of the water is lost in pipe leakages. In fact, most city dwellers in developing countries are forced to boil their water or to buy bottled water, which is very expensive.

There are several actions that could be taken to eradicate the problems described above. Firstly, a simple solution would be joining community efforts to address problems affecting your city. Ask your parents, friends and relatives to join in as well. These efforts might include clean-up campaigns, recycling projects and a signature campaign to ask the government to do something about the situation. A second measure would be encouraging your teacher to talk about these problems and to discuss how young people can help to solve them. Finally, writing to local organizations working on these issues for ideas on how you can contribute to solve them.

The word tackle in paragraph 1 is closest in meaning to ____.

Most workers seem (A) to be happy with (B) its new (C)  working conditions (D).

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 26 to 30.

     Why is it that many teenagers have the energy to play computer games until late at night but can't find the energy to get out of bed in time for school? According to a new report, today's generation of children are in danger of getting so (26) ___________sleep that they are putting their mental and physical health at risk. Adults can easily survive on seven to eight hours' sleep a night, (27) ___________teenagers require nine or ten hours. According to medical experts, one in five youngsters gets anything between two and five hours' sleep a night less than their parents did at their age.

     This (28) ___________ serious questions about whether lack of sleep is affecting children's ability to concentrate at school. The connection between sleep deprivation and lapses in memory, impaired reaction time and poor concentration is well (29) ___________Research has shown that losing as little as half an hour's sleep a night can have profound ef fects on how children perform the next day. A good night's sleep is also crucial for teenagers because it is while they are asleep (30)___________they release a hormone that is essential for their 'growth spurt' (the period during teenage years when the body grows at a rapid rate). It's true that they can, to some extent, catch up on sleep at weekends, but that won't help them when they are dropping off to sleep in class on a Friday afternoon.