The normal stress and shear stress at failure on the failure plane are 10 kPa and 4 kPa respectively, then the angle of internal friction of the soil and the angle of the inclination of the failure plane to the major principal Plane are _____, ______
1
21°48', 55°54’
2
55°54', 21°48’
3
10°54’, 50°27'
4
50°27', 10°54'