一Dad, would you please drive ?
一No hurry. We have enough time before the plane takes off.
A:faster
B:more slowly
C:more carefully
- What do you like? – I like ____.
若两个非零向量a→,b→满足|a→+b→|=|a→-b→|=2|a→|,则向量a→+b→与a→-b→的夹角是 )
学习知识要一点一滴,善于积累, ;平凡的努力虽不惊人,却能攀登万仞高峰。