Q1: The coefficient of curvature for a well graded soil, must be between

ANS:B - 1.0 to 3.0

For single grained soil cu & cc =1.
Well graded soil cu= 5 & 1<cc<3.
Uniform Soil cu<3.
cc is curvature coefficient.
cu is uniformity coefficient. The coefficient of curvature is the ratio (D30) 2/ (D10. D60) , where D60, D30, and D10 are the particle diameters corresponding to 60, 30 and 10% finer on the cumulative particle-size distribution curve, respectively.