题型：问答题 简答题 2011年5月食品塑化剂事件引起社会的高度关注．常用塑化剂的学名“邻苯二甲酸而（2-乙基己）酯”，化学式为C24H38O4，它是一种无色透明的液体，有特殊气味，不溶于水，溶于大多数有机溶剂，有毒．常用作各种塑料制品的工业添加剂，不可食用．可是黑心业者为了牟取暴利竟然将其添加到多种饮料、果冻、果酱和方便面等食品中．若长期食用此类食品可能对生殖系统、免疫系统造成危害，大量摄入还可能致癌．请分析上诉信息，回答下列问题：（1）以下对于C24H38O4的分析正确的是______；①该物质是有机化合物②该物质中含有24个碳原子③该物质由碳、氢、氧三种元素组成④该物质中碳、氢元素的质量比为12：19（2）写出该塑化剂的两条物理性质______；（3）下列做法，可以使我们远离塑化剂的是______；①少喝各种饮料，日常饮水以白开水为主②经常吃方便面、面包等速食食品以适应我们快节奏的生活③尽量少用塑料制品直接接触热的、含油脂的食物④呼吁政府完善食品安全监督检验机制，严惩不法黑心业者（4）请你再写出一条远离塑化剂的做法______． 查看答案
题型：问答题 简答题 多个环境因素对政策的影响，不仅表现在共同作用上，而且还突出地表现在（）作用上。这种作用常常会引起预料不及的连锁反应，使得问题变得更加复杂。A.个别B.联系C.交叉D.个体 查看答案
题型：问答题 简答题 质量为m=1.0 kg的小滑块（可视为质点）放在质量为M=3.0 kg的长木板的右端，木板上表面光滑，木板与地面之间的动摩擦因数为μ=0.2，木板长L=1.0 m。开始时两者都处于静止状态，现对木板施加水平向右的恒力F=12 N，如图所示，经一段时间后撤去F。为使小滑块不掉下木板，试求：水平恒力F作用的最长时间。（g取10 m/s2） 查看答案
题型：问答题 简答题 The first 50 years of the next millennium will be critical for the world’s population. By 2050 population growth should have leveled off, but by then we’ll have 10 billion people -- two-thirds as many again as we have today. The rate of population growth is something we can choose right now, though it’s not something that just happens, but a matter of human choice. The choice is a complicated one, with many variables, but it remains a choice. If we want to prevent a population explosion, we should take action now -- or assist the poorer countries to do so. They need better government, better institutions, better labor and capital markets, better schools. Anything that increases the value of women’s time and adds to the cost of caring for a child makes a woman less likely to have that child. Since big families are often seen as safety nets for illness and old age, improving poor people’s access to insurance, pensions and welfare institutions also has a major impact. This can be as simple as rural credit, providing a means of saving. Finally, there is education -- both for women and, perhaps even more important, for the next generation of children. These steps are there to be taken, but there appear to be some countries that are not seriously trying at the moment. If we cannot achieve that we will certainly not control population. That said, I don’t feel pessimistic that we are going to run out of resources: we are becoming more efficient at producing food faster than the rate at which population is increasing. There is, however, a risk that we will wreck the environment so effectively that the world will no longer be an attractive place to live. That really would be a dismal outcome, to reach world population equilibrium only to find we’d destroyed the natural environment in the process.The author insists that the control of population should not be at the cost of ______.A．sacrificing the poor people’s welfareB．losing something equally preciousC．improving the environmentD．reaching the equilibrium of population 查看答案
