Please draw the mohr curcle either by hand or electronically so I can see how the calculations are done. Thank yoy kindly!

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$8\mathrm{.}25$ In a direct shear test on a specimen of cohesionless sand, the vertical normal stress on the specimen is $5000$ psf and the horizontal shear stress at failure is $3300$ psf$.($a$)$ Assuming uniform stress distribution within the failure zone and a straight line failure envelope which goes through the origin, determine by means of the Mohr circle the magnitude and direction of the principal stresses at failure. $($b$)$ Explain why it is not possible to determine the principal stresses in a direct shear specimen for an applied horizontal shear stress which is not large enough to cause failure. $($After A$.$ Casagrande.$)$