题目

New energy-sharing projects _____ in dozens of cities across the country to fuel China's sharing economy in the next few years. A . are to carry out B . are being carried out C . were carried out D . will have been carried out 答案：B已知函数的图象是曲线C，直线与曲线 C相切于点（1，3）. （1）求函数的解析式； （2）求函数的递增区间； （3）求函数上的最大值和最小值.