（附加题）若A=3m2-5m+2，B=3m2-4m+2，试分析A与B的关系。
解：
，
当m＜0时，A＞B；
当m=0时，A=B；
当m＞0时，A＜B。
我国不是气团的源地而多锋面活动，为什么？
Which of the following statement is INCORRECT（）。
A. The British constitution includes the Magna Carta of 1215.
B. The British constitution includes Parliamentary acts.
C. The British constitution includes decisions made by courts of law.
D. The British constitution includes one single written constitution.
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