Please answer the question without Excel solver.

a 2. The manager of a Job-Shop needs to assign 4 jobs to 4 workers. The cost of performing a job is a function of the skills of the workers. The Table below summarizes the cost of the different assignments. Worker A cannot do job 3 and worker C cannot do job 4. Find the optimal assignment of workers to the different jobs, and compute the associated cost. Job 3 1 2 4 A B $20 $30 Worker $50 $70 $90 $70 $50 $40 $30 $20 $20 $50 $60 D $70