Fig. $23\mathrm{.}1$ Consider the soil whose PSD curve is shown in the figure below. The soil has plastic limit

$(PL)=20\%$ and liquid limit $(LL)=65\%.$

Answer the questions below. You may refer to the USCS table where necessary.

a$.$ What is the fines content of the soil?

b$.$ According to the USCS, is the soil coarse$-$grained or fine$-$grained?

c$.$ What is the plasticity index of the soil?

d$.$ Calculate D$60,$ D$30,$ and D$10.$

e$.$ Compute the coefficient of uniformity $(Cu)$ and the coefficient of curvature $(Cc).$

f$.$ In the plasticity chart, do the Atterberg limits of this soil plot above or below the A$-$

line? Justify your answer.

g$.$ Classify the soil according to the USCS. Clearly explain each step of the classification

process until you arrive at the group symbol$($s$).$