题目

 The happy smile on her face suggests that she _______ to the party tomorrow evening. A. is about to   B. should go      C. will go       D. would have gone    答案：C9．（1）在等差数列{an}中，d=2，n=15，an=-10，求a1及Sn．（2）在等比数列{an}中，已知a1=-1，a4=64，求q及S3．