A steel tensile specimen $($Elastic Modulus, E$=209$ GPa$)$ has a circular cross$-$section with $12\mathrm{.}83$ mm

minimum diameter and a $50$ mm gage length. In a tensile test of this specimen, maximum load is

reached at $6818$ Kg and fracture occurs at $4546$ Kg$.(3$ points$)$

Based on the data provided above, answer the following questions:

$($a$)$ What is the maximum tensile strength?

$($b$)$ Why does fracture occur at a lower load than at the maximum load?

$($c$)$ What is the elastic deformation when a tensile stress of $103$ MPa is applied?