在显微镜的结构中，与调节光线强弱有关的结构是____和____．

从国内到国外再回国内，经过8300多个日日夜夜的孜孜以求，河南药学家、河南师范大学校长常俊标和他的团队捧出了四种具有自主知识产权的原研药——治疗艾滋病、脑梗、肝癌和丙肝的药。这体现了实践（   ）。

①是按照主观的内在本性改造世界   

②是一种直接现实性活动

③是客观见之于主观的能动性活动   

④具有社会历史性的特点

关于我国是世界资源大国的各种叙述，正确的是（  ）

      Yesterday when my son and I were eating dinner, I saw a policewoman walking past our house. A woman with a1look was following her.
      I opened the 2 , went out and asked if everything was OK. The policewoman said that the woman's3 had gone missing(失踪) an hour earlier. I said that we hadn't seen the girl, but wecould4.Iexplained to my son that we couldn't finish our5 right then. He said,” Be a kind person, Dad. "We got in our car and6 the girl all over the town. Along the way,a group of chil­dren were playing.  7they heard what had happened, they said they would help8 . They rode their bikes and joined us. 9 the little girl was found safe a few miles away. I was so 10to see many people help a stranger. It is a nice world.

某同学用托盘天平和量筒测量一小块岩石的密度．他调节天平时出现了图甲所示情形，他应将平衡螺母向____ （选填“左”或“右”）移动使天平平衡．然后他用天平测量矿石的质量，示数如图乙所示，则矿石的质量为____ g．若将该岩石带到月球，其质量____ （选填“变大”、“变小”或“不变”）．最后他用量筒测量岩石的体积，示数如图丙所示，由此可得矿石的密度为____ kg/m³．

做完试验后，该同学想用类似的方法测量一杯液体的密度，步骤如下：

①测量空烧杯的质量；

②测量烧杯和液体的总质量；

③将烧杯中的液体倒入量筒中测出液体的体积；

④利用密度公式计算出液体的密度．

（1）上述测量过程会导致测得的密度值____ （选填偏大、偏小、不影响）．

（2）为了使测量值更精确，上述测量顺序可调整为：____ （填写序号）．