用显微镜观察临时装片时，发现视野中有一污点，这个污点不可能存在于（  ）

________，he couldn't solve the problem. So he turned to his friend for advice.

    Hello ,my friends.I 1_free this Sunday. We have no classes. I would like 2 out tor a picnic with my family on the farm. My mother and I do some shopping3 the morning. My mother buys some4,like bread and chicken . I buy5bags of milk. A bar of chocolate needs 11 yuan , but I buy five 6 50 yuan. Bananas are my7 I take a lot of bananas with 8.On the farm we see many rabbits. They are very9.I like them very much. We are all 10  on that day.

小红喜欢折纸，一天下午，她用一张长24厘米、宽14厘米的长方形折纸，她想折一个最大的正方形，你帮帮她，这个最大的正方形边长是____厘米。