【正确答案】e=d_sγ_w(1+w)/(γ-1)=2.69×10×(1+0.29)/(18.62-1)=0.864
   n=e/(1+e)=0.864/(1+0.864)=46.4/%
   S_t=wd_s/e=0.29×2.69/0.864×100/%=90.3/%
   γ_sat=(W_s+V_vγ_w)/v=(d_s+e)γ_w/(1+e)=(2.69+0.864)×10/(1+0.864)kN/m³=19.07kN/m³
   γ_d=γ/(1+w)=18.62/(1+0.29)kN/m³=14.43kN/m³
   γ'=γ_sat-γ_w=(19.07-10)kN/m³=9.07kN/m³