Q$1.$ Assuming that the clay soil has a yielding function as the following:

$(p^{\text{'}}{)}^2-p^{\text{'}}{p}_c^{\text{'}}+\frac{q^2}{M^2}=0$

where $p^{\text{'}}$ is the mean effective stress, and $q$ is the deviatoric stress. $p_c^{\text{'}}$ is the effective preconsolidation stress. $M$ is the material property. A clay soil was consolidated to a mean effective stress of $).$ If $M=1,$ plot the yielding curve in the $p^{\text{'}}-q$ space.