两拉杆的材料和所受拉力相同,且均处在弹性范围内,若两杆长度相等,横截面面积A1>A2,则:()
A.A
B.B
C.C
D.D
参考答案:C
解析:
—Oh, no ! There is no sugar left .
—_____. I’ll buy some when I go into town.
A ,Good idea B. Not at all C. Never mind