四边形ABCD为菱形,∠A=60°,对角线BD长度为10cm,则此菱形的周长______cm.
由已知可得△ABD是等边三角形,
∴AB=BD=10cm,
则此菱形的周长40cm.
饵兵运动的发起国是()
A.宋
B.郑
C.晋
D.魏
—It's time to go to bed, Li Ping.
—Mum, I have a lot of homework to do, I won't go to bed ________ I finish it. [ ]
A. until
B. since
C. as soon as
D. after