Cone penetrometer soundings were used for the subsurface investigation of a planned construction site. At one sounding location, the value recorded for q c at a depth of 8 m was 8,000 kPa. The soil...

Cone penetrometer soundings were used for the subsurface investigation of a planned construction site. At one sounding location, the value recorded for q_c
at a depth of 8 m was 8,000 kPa. The soil has a unit weight of 16 kN/m³. Using criteria that relate CPT results and the soil angle of internal friction, estimate the value of f for the sand at the test depth.