阅读理解
Age plays a major part in people who are infected with cold,ie,in people who suffer from cold
infection.A study done by University of Michigan,has shown information that seems to be true for the
general population.Babies are the most cold infected group,generally more than six colds in their first year.Boys have more colds than girls up to the age of three.After three,girls are easier to get infected with cold
than boys,and teenage girls get three colds a year to boys' two.The general cold infections continue to get
less into adults.Elderly people who are in good health have as few as one or two colds every year.One
interesting thing is found among people in their twenties,especially women,who show a rise in cold
infection,because people in this age group are most likely to have young children.
The study has also found that economy plays an important role as well.With more and more income,
the frequency at which colds are reported in the family is getting lower and lower.Families with the lowest
income usually suffer about a third ally forces people to live in rooms more crowded than rooms owned by richer people,and the crowding usually leads to more chances for the cold virus to travel from person to
person.Low income may also have an effect on our diet.Many scientists believe that a poorer diet usually
leads into more possibilities of cold infection.
1．Which of the age groups has the highest frequency of cold infection?
A．Small babies.
B．Teenage boys.
C．Adult women.
D．Elderly people.
2．The purpose of writing this passage is to________.
A．give the readers some tips to avoid cold infection
B．show a carefullmade study on cold infection
C．report the major reasons leading to cold infection
D．describe all the possible dangers of cold infection
3．How does economy play an important role in cold infection?
A．Families with lower income suffer less from cold infection.
B．People who have lower income enjoy living in crowded rooms.
C．Rich families can have better nutrition and never get infected.
D．People with higher income have fewer chances of infection.
4．From the passage we can infer that________.
A．age is the only important factor that connects with colds
B．families with the highest income will more easily get infected
C．people have lower frequency of infection as they grow older
D．a better diet may help people to fight against cold infection
2NO+O2反应。反应过程中NO2的物质的量随时间变化的状况如图所示。
