Trucks arrive at the loading dock of a wholesale grocer at the rate of 1.2 per hour. A single crew consisting of two workers can load a truck in about 30 minutes. Crew members recelve $10 per hour in wages and fringe benefits, and trucks and drivers reflect an hourly cost of $69. The manager is thinking of adding another member to the crew. The service rate would then be 24 trucks per hour. Assume rates are Poisson. Use Table 1 and Table? 10 0. Would the third crew member be economical? (Round your intermediate and final answer to 2 decimal places.) b. Would a fourth member be justifiable if the resulting service capacity were 3 trucks per hour? (Round your intermediate ond final answer to 2 decimal places.)