读图，人类认识地球形状的先后过程是（    ）

探究学习小组在制作“叶脉书签”时，需要将树叶放在质量分数为10%的氢氧化钠溶液中煮沸，如图1所示为该小组配制10%的氢氧化钠溶液的操作过程：

在方框中填入一个恰当的词、或填入所给单词的适当形式，使短文通顺、正确、连贯。
    A lot of people wish to be slim, but at the same time they are____（worry）about their health. In fact, it is important for everyone to lose weight healthily. A strong body can keep you working in a high speed and make you more positive every day. However, how can you do it? Here's some good____（advice）.
    ●Drink plenty of water and eat____healthy diet. If you feel like____（eat）snacks, drink a glass of water first. If you are still hungry after 15____（minute）, then it's time for a light snack. Try to stay away from food with high calories, such as sweets and fast food.
    ●Do not eat____(much) than you can consume (消耗). People get fat because they can’t consume all the calories ____they get. So, knowing how many calories you really need is very important.
    ●Take enough exercise.  The  “333” is good   for you—exercise three____(time) a week, for at least 30 minutes at a time, and your pulse rate (脉搏率) should be more than 130 after____(exercise).
    Keep the three pieces of advice in mind and follow the advice. Then you'll____(sure) have a slim and strong body.

一个静止质量m₀＝1 kg的物体，与地球一起绕太阳公转的速度为30 km/s，在相应的惯性参考系中，观测者测得该物体的质量为多少？

如图所示为一个无盖长方体盒子的展开图（重叠部分不计），根据图中数据，可知该无盖长方体的容积为（　　）