2a=a2．______．（判断对错）
2a=a×2，a2=a×a，所以2a≠a2．
故答案为：错误．
—______ do you get up so early(早)?
—______ I want to take the early bus to school. [ ]
A. Why; So
B. What; So
C. Why; Because
D. How; Because
饲用玉米应在什么时候收获较好？
