The prevent and treatment of AIDS is the field where we can ()(合作).
第1题
____________prevent a lot of radiation damage
[A] get
[B] make
[C] have
[D] do
第2题
A.contact
B. contrast
C.connection
D.conflict
第3题
Can we ever _____ hunger from the world?A. eliminate B. throw C. stop D. prevent
第4题
gases from escaping.
A) fruitful B) beneficial
C) valid D) effective
第5题
A.contact
B. contrast
C.connection
D.conflict
第6题
第7题
(1)至少一个周六晚上不能在家过夜的旅客才可以购买特价机票。
(2)坚持将水泥送货上门,并以购买者的住址为定价基础。
(3)销售食品加工机时附送10美元折扣的优惠券。
(4)对卫生纸提供临时促销价。
(5)给高收入病人做整形外科手术的要价高于低收入病人。
Price discrimination requires the ability to sort customers and the ability to prevent arbitrage. Explain how the following can function as price discrimination schemes and discuss both sorting and arbitrage:
a. Requiring airline travelers to spend at least one Saturday might away from home to qualify for a low fare.
b. Insisting on delivering cement to buyers, and basing prices on buyers' locations.
c. Selling food processors along with coupons that can be sent to the manufacturer to obtain a S 10 rebate.
d. Offering temporary price cuts on bathroom tissue.
e. Charging high-income patients more than low-income patients for plastic surgery.
第8题
Biologists today don’t expect that anyone will find a magical fountain of youth.Growing older is a natural part of the life cycle that can’t be reversed.As human beings grow older, organs such as the heart and lungs may stop functioning properly.Sight and hearing may become weak.And the human body becomes more likely to come down with serious illnesses from which it cannot recover.
Considered together, changes that bring about the decline of an organism are called aging.Because of aging, many biologists believe that there may be a maximum age limit to which even the healthiest organisms can live.For human beings, this maximum age limit is about 110 years.
Perhaps the most important thing that you can learn from your study of human biology is that you have a lot of control over the aging process in your own life.In fact, within our control are many physical and mental factors that have much to do with aging.For example, each of us, as recent research indicates, can do many things to help prevent heart and vessel disease, which causes half the death each year in the United States.We can avoid eating a lot of fatty meat.Eating too much of these types of animal fats can lead to the clogging and hardening of blood vessels.We can cut back on smoking and hopefully quit entirely.We can limit the amount of alcohol we drink and the amount of sugar we eat.We can exercise regularly and strengthen the heart and other organs.And we can remember to take time out each day for ourselves, time just relax.Exercise, recreation and relaxation all reduce stress – inner tension that is hard on all body organs.
One final thing we can do is to try to keep aware of advances made in health education.Information is often available free of charge from health clinics or schools.
1.Which of the following is the leading cause of death in the United States?
A.Heart disease.
B.Cancer
C.Alcohol
D.Smoking
2.What happens as people grow older?
A.They dream of a magic pill to help them live a happy and long life
B.They come down with serious illnesses
C.Their organs become weak and may stop working properly
D.Their blood vessels become clogged
3.In the opinion of biologists, _________.
A.the aging process can be reversed
B.the aging process can be controlled and slowed down
C.the aging process can be got rid of
D.the aging process can go beyond its limit
4.We can slow down the weakening of all our body organs by ______.
A.not eating animal fat
B.limiting drinking and smoking
C.exercise, recreation and relaxation to reduce stress
D.preventing the clogging and hardening of blood vessels
5.Besides physical and mental factors, which of the following also contributes to living a long and healthy life according tot the passage?
A.Health education
B.Traditional medicine
C.artificial organs
D.The invention of magic pills