首页
登录
职称英语
What happens to trees each year? [br] [originaltext] During this century, a
What happens to trees each year? [br] [originaltext] During this century, a
游客
2023-11-14
11
管理
问题
What happens to trees each year? [br]
During this century, archaeologists have discovered that the trees can be a valuable tool for measuring time. In scientific terms, this method is called dendrochronology. Dendrochronology is based on the scientific discovery that each year a tree grows a new layer of wood. When you cut down a tree, for example, you can see and count the layers of concentric circles. These circles will reveal a great deal of information. The layers vary in color and in thickness. These variations are a result of differing climate conditions from year to year that affect the growth of the annual rings. Cold weather, for example, creates thinner and lighter rings while hot weather produces thicker and darker rings. All trees that grow in the same region will have roughly the same pattern of annual rings, and this can be used as a source of comparison and measurement.
Early in this century, archaeologists began using the rings to date ruined structures and figures built in the southwestern United States. They did this by comparing the rings of the wood found in the ruins with the rings of recently cut trees. Slowly but surely, the system was extended backwards in time to measure older ruins. The heavy forestry of the United States, coupled with the relative youth. Of its history, led to a fairly uncomplicated study. Eventually, dendrochronology produced an accurate time and weather record for the American southwest that extended over 2,000 years.
选项
A、It began 2000 years ago.
B、It began in the eighteenth century.
C、It began in the early twentieth century.
D、It began in this decade.
答案
C
解析
原文中有“Early in this century, archaeologists began using the rings to date ruined structures and figures built in the southwestern United States”一句。
转载请注明原文地址:https://tihaiku.com/zcyy/3187208.html
相关试题推荐
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcen
随机试题
Whenwethinkofoil,thepartoftheworldthatcomestomindfirstmaybe
失望的生理表现有A.体重减轻 B.食欲减退 C.睡眠紊乱 D.挫败感 E
甲公司委托乙公司加工应税消费品,则下列说法正确的有()。A.甲是增值税的纳税义务
在完全电流差动保护的原理接线图中,对母线上所装设的电流互感器的要求是()A
内部审计活动的外部评估通常不涉及以下哪项?()A.对内部审计活动的章程的遵守
()是企业生产控制的基础工作,是对生产过程中各工序原材料、半成品等所处位置
以下关于消防水泵操作控制的说法中,不正确的是()。A.当消防给水分区供水采用串联
世界上最早的智力测验是()。
下列说法中,正确的是( )。A.大赦既赦其刑,又赦其罪B.特赦只赦其刑
Questions59-61refertothefollowingl
最新回复
(
0
)