A:an hour or two
B:one or two hour
C:one and a half hour’s time
D:one hour and a half time
She tried to finish all the work in one day but finally _____ and had to take a rest.
下图为“1959~2009年秦岭山地1月0℃等温线位置变化图”。回答下面小题
若方程6a2-a-2x+3a2-5a+2y+a-1=0表示平行于x轴的直线,则a的值是( )