2a7a10a1348的精选

问题详情：已知等差数列{an}，且3（a3+a5）+2(a7+a10+a13)=48,则数列{an}的前13项之和为（   ）A.24      B.39          C.104           D.52【回答】D知识点：数列题型：选择题...