Refer to Figure 1. Given: y = 17.5 kN/m3, c = 30 kN/m2, and center-tocenter spacing of struts in the plan = 5 m. Draw the earth-pressure envelope and determine the strut loads at levels A, B, %3! and C. Figure 1 6 m m 3 m c = 30 kN/m2 B y = 17.5 kN/m 2 m C I m