A:甲苯
B:乙酸乙酯
C:溴苯
D:苯
He said he was very sorry because it was _______ his power to make the final decision. _______, I had to turn to others for help.
如图,有一个与地面成30°角的斜坡,现要在斜坡上竖一电线杆,当电线杆与地面垂直时,它与斜坡所成的角α=____°.
归园田居(其三)
陶渊明
种豆南山下,草盛豆苗稀。
晨兴理荒秽,带月荷锄归。
道狭草木长,夕露沾我衣。
衣沾不足惜,但使愿无违。