maxx1+2x2+4x3+x4s.t.:x12x31x2x462x1+x2+8x3+x412x1,x2,x3,x40 a) What is the optimal solution and the optimal value of the objective function? b) What is the optimal objective function of the dual problem? Provide your answer based solely on the given reports, without any further calculation. c) Suppose that the objective function changes to f(x)=0.8x1+1.5x2+5x3+x4. Use the 100% rule to check if this change will affect the structure of the given solution. What if the objective function changes to f(x)=0.8x1+1.5x2+6x3+x4