Luisa ___________ una taza de té y empezó a leer.
A.se servía
B.se sirvió
C.sirvió
D.servía
A.se servía
B.se sirvió
C.sirvió
D.servía
A.中国科学院地质所谷德振提出的分类是将岩体按结构类型分为整体块状结构、层状结构、裂隙结构和散体结构四大类和八亚类
B.挪威的Q系统分类法包括6个基本参数,由参数取值表查出并计算Q值,Q值的范围为0.001~1000,从极差到极好分为9个等级
C.地质力学分类法又称RMR或CSIR分类法,包括5个基本参数,分别为岩石材料的单轴抗压强度、RQD、节理间距、节理状况和地下水状况
D.新奥法被认为是近代隧洞工程技术中一种比较落后的方法,因为它在概念上把围岩看做地下洞室承载结构的一部分,支护只是给围岩承载力不足部分的补充和强化
3. Rabbits in Australia Rabbits were introduced to Australia with the arrival of the First Fleet in 1788. Within 50 years rabbits had spread throughout the most of the continent with devastating impact on indigenous flora and fauna. Large numbers of rabbits were reported around Geelong in 1869 and around Campebell Town in Tasmania later the same year. A large scale plague occurred in 1871 throughout parts of Tasmania starting prior to March, with farmers using strychnine in an attempt to control numbers and continuing through to May of the same year. In 1876 a plague was reported in districts around Kapunda in South Australia with a commission being established to find the cause and suitable methods of control of the problem. Areas between the Riverina through to the Mallee country and Charlton were being plagued by large numbers of rabbits in 1877 and 1878. The Rabbits Nuisance Suppression Bill was introduced into the Parliament of Victoria in an effort to combat the problem. By 1878 and early 1879 the plague had spread into northern areas of South Australia Numbers of rabbits in the affected areas were still considered problematic through the 1880s and 1890s. Large numbers of the pest were still found throughout parts of Victoria, New South Wales, South Australia and Western Australia through the early 1900s while the areas were also gripped by drought. After the drought broke in around 1904 numbers of rabbits and mice started to grow again in the same areas as well as parts of Queensland to plague proportions. Following a reduction in numbers during the drought of 1914 to 1915, plagues of rabbits were reported in 1918 through parts of South Australia and western New South Wales. In 1932 and 1933 rabbits again bred up in large numbers in parts of New South Wales, South Australian and Victoria causing massive damage to crops and feed. Field trials for the myxomatosis virus were carried out in 1936 by the CSIR Division of Animal Health and Nutrition, as a method of controlling rabbit population. The trials were successful in killing rabbits in their warrens but did not spread well between warrens. By 1946 another plague was being predicted by graziers following a drought breaking, and numbers of rabbits started to rise in 1948 and continue into 1949 and 1950 causing massive damage to crops in parts of New South Wales, Victoria and South Australia in a plague described as the worst rabbit plague in Australia's history. The myxomatosis virus was released in 1950 to reduce pest rabbit numbers. It initially reduced the wild rabbit population by 95% but since then resistance to the virus has increased. 5. What contributed to the reduction of the number of wild rabbit?
A、The Rabbits Nuisance Suppression Bill.
B、The drought.
C、Myxomatosis virus.
D、Strychnine.
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