The mechanical properties of a metal may be improved by incorporating fine particles of its oxide. Given that the moduli of elasticity of the metal and oxide are, respectively, 60 GPa and 390 GPa, what is the (a) upper-bound, and (b) lower-bound modulus of elasticity values (in GPa) for a composite that has a composition of 70 vol% of oxide particles. (a) Enter your answer for part (a) in accordance to the question statement GPa (b) Enter your answer for part (b) in accordance to the question statement GPa