题型：问答题 简答题 在数列{an}中，an+1=an+a（n∈N*，a为常数），若不共线的非零向量OA，OB，OC满足OC=a1OA+a2010OB，三点A，B，C共线且该直线不过O点，则S2010等于______． 查看答案
题型：问答题 简答题 — What is our head teacher like,do you know?— Oh,he is very kind _____ he looks very serious.[ ]A. because B. though C. if D. when 查看答案