Q$3)$ Let S $=\{$a$,$ b$,$ c$,$ d$,$ e$,$ f$,$ g$\}$ be a collection of objects with benefit$-$weight values, a:

$(12,4),$ b : $(10,6),$ c : $(8,5),$ d: $(11,7),$ e: $(14,3),$ f : $(7,1),$ g : $(9,6).$ What is an optimal

solution to the fractional knapsack problem for S assuming we have a sack that can

hold objects with total weight $18?$ Show your work. Validate the correctness of the

statement $$Greedy approach does not ensure an optimal solution for $0/1$ knapsack

problem$.$