干燥器的再生原理是分子筛在高压低温状态下对脱附水有利。
参考答案:错
不论x为何值时,y=ax2+bx+c恒为正值的条件是( )
A.a>0,△>0
B.a>0,△>0
C.a>0,△<0
D.a<0,△<0
Here are some ______. Do you like ______?[ ]
A. orange; it
B. oranges; them
C. orange; them
D. oranges; it