图示起重机的平面构架，自重不计，且不计滑轮质量，已知：F=100kN，L=70cm，
B、
D、E为铰链连接。则支座A的约束力为：
AFAx =100kN(←)FAy = 150kN(↓)
BFAx =100kN(→)FAy = 150kN(↑)
CFAx =100kN(←)FAy = 150kN(↓)
DFAx =100kN(←)FAy = 150kN(↓)
AFAx =100kN(←)FAy = 150kN(↓)
BFAx =100kN(→)FAy = 150kN(↑)
CFAx =100kN(←)FAy = 150kN(↓)
DFAx =100kN(←)FAy = 150kN(↓)