设f（x）是定义在R上的奇函数，当x≤0时，f（x）=2x2-x，则f（1）= [ ]
A.-3
B.-1
C.1
D.3
答案：A
茄克衫制作的重点和难点是装拉链、装领、装袖克夫。
—I don’t think it very expensive to buy a family computer here.
—Really? I’ll buy _____ next week.
A．it
B．this
C．one
D．mine
