A free bar of length 1 m is uniformly heated from $${0^ \circ }C$$ to a temperature of $${t^ \circ }C$$. $$\alpha $$ is the coefficient if linear expansion and $$E$$ the modulus of elasticity. The stress in the bar is

A large uniform plate containing a rivet-hole is subjected to uniform uniaxial tension of 95 MPa. The maximum stress in the plate is