(a)
Young’s modulus is given by the equation,Y= stress/ strainAt a particular strain, Young’s modulus is directly proportional to the stress.
The slope of stress strain curve for material A has greater than the material B which gives higher value of Young's modulus.
(b)Material B is more brittle since the fracture point (end of solid curve) is at lower corresponding value of stress.
(c) Material A is more ductile since it has a greater plastic region; from elastic limit to breaking point.
(d)The strength of the material depends upon the stress at the fracture point. The fracture strength of material A is more than that of B. Hence, material A is stronger.