A double lap joint transfers a loading comprising of a superimposed dead load of $100$ kN and a superimposed live load of $100$ kN$.$ Using M$168\mathrm{.}8$ bolt and plate of tensile strength $200$ MPa

a$)$ Determine the number of bolts needed for the connection. $(2$ nos$)$

b$)$ Determine the minimum thickness t

of each of the two plates. $(8$ mm$)$