某校化学兴趣小组对雪碧中的气体进行了如下探究，请你回答下列问题：

（1）猜想：雪碧中的气体是二氧化碳

用注射器抽取一定的雪碧，上下振荡，然后将液体部分挤出，收集到一注射器的气体，问：怎样设计实验证明其为二氧化碳：____ ，该反应的化学方程式为：____ 　．

（2）对二氧化碳性质的探究

收集一注射器的CO₂，然后将该气体缓慢的通过如图所示的装置后（图中①、④为用紫色石蕊溶液润湿的棉球，②、③为用紫色石蕊溶液染成紫色的干燥棉球），发现：

①棉球2和3均不变红，这是因为：____ ．

②棉球4比1先变红，说明：____ ．

③棉球1也变红的原因是：____ ．

（3）该小组还注意到：打开雪碧瓶后，立即能观察到有大量气泡产生，这说明二氧化碳在水中溶解的多少与____ 因素有关．

图为巴西示意图和巴西人种构成图，读图完成下列问题。

    Jack Ma is the founder and CEO of the alibaba.com,____ is the biggest e-commerce company in China. The website is an English-language site. It aims to offer suppliers and consumers____ direct means to communicate, and thereby save time and money ____ (efficient). This model of business ____ (refer) to as B2B (business to business), and it has attracted millions of users worldwide. On the back of this success. Jack Ma and his team developed Taobao in 2001. Today, alibaba.com is considered by many to be one of the best B2B____ (site), with over 7 million users____ (come) from more than 200 countries and religions. Jack Ma____ (become) the first Chinese businessman to appear on the cover of the famous magazine Forbes in the past 50 years. Jack Ma is respected by people not just because of his success, but also because of his____ (person). Although modest, Jack Ma is a very ____ (ambition) man. When asked about his future plan, he once said, 'I believe that in the next ten years, ____ the top three Internet companies in the world, one will be from China—and we want to be that company.'

张德彝在《航海述奇》里记载了1866年他从天津到上海途中吃西餐的事情：“每日三次点心，两次大餐……所食者，无非烧炙，牛羊鸡鱼，再则糖饼、苹果……饮则凉水、糖水、热牛奶、菜肉汤、甜苦洋酒。”材料说明当时