Answer the following descriptive questions.

a. Explain the relationship between performance, objective, and constraints in design optimization.

b. Explain the usage of a knockdown factor in calculating allowable strength.

c. Based on 10 coupon tests, the strength of material A is normally distributed by \(N(500\), \(40^{2}\) ), while material B is by \(N\left(480,20^{2}\right)\). Which material has a higher Bbasis allowable strength?

d. In structural design, why do we need to consider both the allowable strength and the safety factor simultaneously?

e. When a truss is statically determinate, how many iterations would be necessary to obtain the fully stressed design? Explain why.

f. If a beam structure is modeled using 3D solid elements and if the crosssectional geometry is design, is it sizing design or shape design?

g. What are the three steps of optimization formulation?

h. Write the standard form of an optimization problem.

i. At an optimum design, the gradient of the objective may not be zero. Explain in what situation that will happen.