【简答题】Read Para.3 and answer the following questions: 1. How many plastic bags are used every day in China? 2. How many of these become litter ? 3. What are they made from? 4. Where do they go? 5. What are ...
【单选题】A young woman enters puberty with approximately 40,000 primary oocytes in her ovary.About how many of these primary oocytes will be ovulated over the entire reproductive life of the woman?