时间t
50
110
250
种植成本Q
150
108
根据表中数据，下列函数模型中可以描述西红柿的种植成本Q与上市时间t的变化关系的是（ ）
A：Q=at+b
B：Q=at2+bt+c，0＜a＜
C：Q=a•bt
D：Q=a•logbt
马路很宽敞，是玩耍的好地方。 （ ）
— What time do you often do your homework?
— We do ________at 7:30 p. m.
2角=____元
— Tim, how do your parents like pop music?
— _____ my dad ______ my mom likes it. They both prefer classical music.
