题目

High school students spent       money on newspapers and magazines in order to improve their grades.        A．a number of     B．a great many    C．a great deal of  D．a good deal 答案：C已知函数f（x）=x2+2x+alnx（1）若f（x）是区间（0，1）上单调函数，求a的取值范围；（2）若?t≥1，f（2t-1）≥2f（t）-3，试求a的取值范围．