题目

— _____ heavy the rainstorm is!—Yes, the town has experienced the most serious flood during the past ten years. A . How B . What C . How a D . What a 答案：A已知函数f（x）=ax+bx+2在区间（-2，+∞）上为增函数，求实数a与b的关系，并证明你的结论．