题型:单项选择题 一均质杆AB重W=30N,长100cm被悬于竖直的两墙之间,不计摩擦,则墙面的反力为()。A.NA=NB=10kNB.NA=NB=20kNC.NA=NB=30kND.NA=NB=40kN 查看答案
题型:选择题 All of a sudden it came to me ________ I might help wash my mom’s feet on Thanksgiving Day. A.if B.when C.which D.that 查看答案