共用题干
第一篇

Exercise Lowers Employers' Health Costs

Companies can save millions in health-care costs simply by encouraging their employees to exercise a little bit,researchers reported on Friday.
They said obese（肥胖的）employees had higher health-care costs , but lowered those expenses by exercising just a couple of times a week一without even losing any weight.
Feifei Wang and colleagues at the University of Michigan studied 23,500 workers at General Motors.
They estimated that getting the most sedentary (惯于久坐的）obese workers to
exercise would have saved about$790,000 a year,or about 1.5 percent of health-care
costs for the whole group.
Company-wide,the potential savings could reach$7.1million per year,they reported
in the Journal of Occupational and Environmental Medicine.
Of the whole group of workers,about 30 percent were of normal weight,45 percent
were overweight（超重的）,and 25 percent were obese. Annual health-care costs
averaged$2,200 for normal weight,$2,400 for the overweight,and$2,700 for obese
employees.
But among workers who did no exercise,health-care costs went up by at least $100 a
year,and were $3,000 a year for obese employees who were sedentary.
But adding two or more days of light exercise一at least 20 minutes of exercise or work
hard enough to increase heart rate and breathing一lowered costs by on average$500 per
employee a year,the researchers found.
"This indicates that physical activity behavior could reduce at least some of the harmful
effects of excess body fat,and in consequence,help lower the health-care costs,"Wang
and colleagues wrote.

How many workers in General Motors were NOT of normal weight?
A:Seventy percent'
B:Thirty percent.
C:Forty-five percent.
D:Twenty-five percent.