【题目】whether the canned food is the factor that contributes to the lead poisoning and the death of crew in Kaship。
1. The lead that was carefully stilled to the can would not contact the food.
2. No other evidence of death of the crew was found in other ship.
3. Water purification system may be the source of poisoning.
1. Company has limited time to finish this work. Workers are under time pressure and it is reasonable that they are careless and apply lead to the cans in a hurry way.
2. First, it is difficult to judge whether sailors are affected by lead without careful tests. Second, the symptoms of lead poisoning are common, such as feeling tired or headache and they can be easily overlooked.
3. The water in the purification system is used for ship engineering since the salt water cannot be used. The water for cooking and drinking comes from a different way.
1. 第一个理论：没有帮助。因为植物没有internal heat,在遇到冷的天气，尤其是冰点以下时不能避免冻害。
话题分类：Natural Phenomenon 属性：小范围核心预测
1. Protection against cold (losing heat).
2. Protection against fungal spores infection, block out water so insects have meanings of fungal infection.
3. Eliminate night time light, in order to track up to the regular time to produce flowers.
1. The plants have no source of internal heating, so whether folding or unfolding suffer the same freezing damage.
2. Even though the plants are folding, they cannot block out all the water and fungal spores only require a few water.
3. Some plants in densely shaded area where no light is reaching still fold their leaves, therefore some other reasons may explain.
【阅读】Three theories to explain how the Mima Mound is formed.
1. Mima Mounds were formed by human labor because they were arranged in order.
2. Mima Mounds were caused by earthquake. After shaking, the land becomes loose and reshape to the Mima Mound.
3. Build by pocket gopher to build nest.
【听力】These three theories are all unconvincing at all.
1. It cannot be created by human labor because there are no human activities and remains to support the theory.
2. Earthquake is impossible to take place in where Mima Mound existed. Besides, there were no enough earthquake to loosen the soil.
3. There are gophers nowadays, but no new Mima Mounds have been found.