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$3.]$ A Three layered flexible pavement is designed for an ESAL $1,{2\mathrm{.}10}^6$ by AASTHO method. $R=95,S_0=0,5,\frac{?}{\text{P}\text{S}\text{I}}=1,5.$ Pavement has a surface layer with a resilient modulus of $390\mathrm{.}000$ psi and thickness $8$ in$.$ Base layer with resilient modulus $21\mathrm{.}000$ psi, thickness $16$ inch. Poor drainage, $1$ month, moisture $1\%.$

Question and determine:

The structural number of the pavement

The roadbed soil res.mod $($MR$)$