One day in the 1 class everyone is busy drawing pictures, but Xiao Ming is doing 2. When the bell rings for break（课间休息）, Xiao Ming gives his 3 to the teacher.

    The teacher looks at it and gets 4. "Why do you give me a piece of paper with nothing on it, Xiao Ming?" 5 the teacher.

    "I'm sorry, sir," says Xiao Ming. "I 6 a dog and some 7 on the paper."

    "Where's the dog and where's the bread?" asks the teacher.

    "I draw the bread 8. When I finish drawing the dog, he9 the bread. When I give it to you, he 10 away," Xiao Ming answers.

在近代西方工业文明的冲击下，新的事物和思想观念影响着中国的社会生活。下表反映的是（    ）

下表是不同温度下水的离子积的数据：

试回答以下问题：

（1）若25＜t₁＜t₂，则a____ 1×10^﹣14（填“＞”、“＜”或“=”），做此判断的理由是____ ．

（2）25℃时，某Na₂SO₄溶液中c（SO₄^2﹣）=5×10^﹣4 mol/L，取该溶液1mL加水稀释至10mL，则稀释后溶液中c（Na⁺）：c（OH^﹣）=____  ．

（3）在t₂温度下测得某溶液pH=7，该溶液显____  （填“酸”、“碱”或“中”）性．将此温度下pH=11的NaOH溶液a L与pH=1的H₂SO₄溶液b L混合．

①若所得混合液为中性，则a：b=____ ．

②若所得混合液pH=2，则a：b=____ ．

读“我国西气东输工程示意图”，回答下列问题。