A tapered circular rod of diameter varying from 20 mm to 10 mm is connected to another uniform circular rod of diameter 10 mm as shown in the following figure. Both bars are made of same material with the modulus of elasticity, E = 2 $$ \times $$ 10⁵ MPa. When subjected to a load P = 30$$\pi $$ kN, the deflection at point A is _______________ mm.

Two triangular wedges are glued together as shown in the following figure. The stress acting normal to the interface, $${\sigma _n}$$ is _____$$MPa.$$

For the beam shown below, the stiffness coefficient $${K_{22}}$$ can be written as

For formation of collapse mechanism in the following figure, the minimum value of $${{P_u}}$$ is $$c{M_P}/L.$$ $${M_P}$$ and $$3{M_P}$$ denote the plastic moment capacities of beam sections as shown in this figure. The value of $$c$$ is ________.