题干
If you work harder, you'll have another______ to play the violin at a concert.
A：sleep
B：chance
C：mistake
D：problem
答案(点此获取答案解析）
B
If you work harder, you'll have another______ to play the violin at a concert.
A：sleep
B：chance
C：mistake
D：problem
的通项公式
，若使得
取得最小值，n=" " （ ）