首页
登录
职称英语
Many people believe the glare from snow causes snow blindness. Yet, with dar
Many people believe the glare from snow causes snow blindness. Yet, with dar
游客
2024-01-22
35
管理
问题
Many people believe the glare from snow causes snow blindness. Yet, with dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snow blindness, when exposed to several hours of "snow light".
The United States Army has now determined that the glare from snow does not cause snow blindness in troops in a snow-covered country. Rather, a man’s eyes frequently find nothing to focus on in a broad expanse of a snow-covered area. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscle aches. Nature balances this annoyance by producing more and more liquid which covers the eyeballs. The liquid covers the eyeballs in increasing quantity until vision blurs. And the result is total, even though temporary, snow blindness.
Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark-colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop searching through the snow-blanketed landscape. By focusing their attention on one object at a time, the man can cross the snow without becoming hopelessly snow blind or lost. In this way the problem of crossing a solid white area is overcomed. [br] To prevent headache, watering eyes and blindness caused by the glare from snow, dark glasses are______.
选项
A、indispensable
B、useful
C、ineffective
D、available
答案
C
解析
细节题。短文第一段第二句指出Yet,with dark glasses or not they findthemselves suffering from headaches and watering eyes,and even snow blindness即不管带不带墨镜,人还是会感到头痛,眼睛变湿,甚至产生雪盲。由此可知墨镜在这种情况下是没有效果的,故选项C正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3384943.html
相关试题推荐
Peoplewholiveinheavilyindustrializedareasdonotgetasmuchsunlight
Peoplewholiveinheavilyindustrializedareasdonotgetasmuchsunlight
Peoplewholiveinheavilyindustrializedareasdonotgetasmuchsunlight
Peoplewholiveinheavilyindustrializedareasdonotgetasmuchsunlight
Peoplewholiveinheavilyindustrializedareasdonotgetasmuchsunlight
ManypeoplewonderwhysomemenwanttoliveonthemoonItis【C1】______not
ManypeoplewonderwhysomemenwanttoliveonthemoonItis【C1】______not
ManypeoplewonderwhysomemenwanttoliveonthemoonItis【C1】______not
ManypeoplewonderwhysomemenwanttoliveonthemoonItis【C1】______not
ManypeoplewonderwhysomemenwanttoliveonthemoonItis【C1】______not
随机试题
A.八正散 B.龙胆泻肝汤 C.前列腺汤 D.知柏地黄汤 E.济生肾气丸
下列各项,属阴道后穹隆穿刺的指征是A.患者处于休克期,临床怀疑腹腔内出血 B.
教师∶教室∶教育 A.经理∶市场∶经商:B.军队∶国家∶保卫 C
左边给定的是多面体的外表面,右边哪一项能由它折叠而成?请把它找出来。 A.如上
城市电力总体规划阶段负荷预测方法中,( )适用于市区内分散的用电负荷预测。A.
某商场三层划分为2个防火分区,防火分区1的建筑面积为3600m2,防火分区2的建
李女士丈夫因车祸去世,她一个人照顾年迈多病的父母和未成年的孩子,与邻居和其他人很
已知条形基础受轴心荷载F=220kN/m,基础埋深1.7m,室内外高差0.45m
单元组合式现浇钢筋混凝土水池工艺流程中,不含()工序。A.土方开挖及地基处理
人类生态环境的危机主要表现A.自然资源和生态环境的破坏 B.人类生存环境的破坏
最新回复
(
0
)