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TRUE or FALSE: Implicit Enumeration is a method for solving problems by asking experts for their best estimate of what to do.

During the pandemic, the valley was experiencing a toilet-paper shortage. You were hired as an engineer at Charmin to help prioritize which cities in the valley should receive their orders first to maximize their profits. The issue is that the one semi-truck you will be loading has a limit on the number of rolls it can hold. The semi-truck can carry 10 rolls from floor to ceiling, 10 rolls from left to right, and 40 rolls from the back to the front of the trailer. You were told by the cities that because of the toilet paper shortage, they are okay with receiving partial orders since their customers are in a stinky situation. Below is each city needing toilet paper, the number of rolls they are requesting, and what the profit is. You will be using a Greedy Knapsack approach to solve this problem.                                                 a. Write the objective function and any constraints for this problem. [5pts]b. Determine the order of which cities you should ship to and list the number of rolls all 6 cities will receive. [5pts] c. What is the total profit? [5pts]

The Daytona 500 racetrack in Florida has some of the best pit-crews in the world to service cars as they race for NASCAR. Each pit crew in NASCAR can contain up to 8 crew members, but only 5 are allowed in the pit at any time. In this scenario, the cars, as they stop, line up and have a crew member assigned. The crew members do not have the same service speed (see table below), but you should assume that all crew members can service a car in full regardless of title (meaning cars do not need to visit all crew members, they are serviced by 1 as they are assigned). Crew Member Pit Speed Tire Carrier 4 cars per hour Utility Man 6 cars per half hour Jackman 5 cars per 15 min Gas Man 7 cars per hour Tire Changer 1 car per 10 min The pit-stop area (nicknamed Tartarus) is where each car is assigned a crew member and are serviced from right to left (meaning the last car is serviced first, then the 19th car and so on). 5a. How many cars can the entire crew serve in 1 hour? (5pts) [PartA] 5b. Identify the order of which the crew members should be placed in the pit (1st, 2nd, 3rd, 4th, 5th). (5pts) [PartB1st] , [PartB2nd] , [PartB3rd] , [PartB4th] , [PartB5th] 5c. Identify which crew member is the bottleneck for the whole pit. (3pts) [PartC]5d. Identify each range of cars the crew members will work when the pit-stop system reaches steady state (REMEMBER: Cars arrive right to left). Please show all work on scrap paper. (10pts) [PartD]

A serial production line will have ten stages. Each stage will fail on average once every 200 cycles with average repair time of 4 cycles. Desired availability is 92%. Which of the following is true of buffers applied to this system?

TRUE or FALSE: Lot Streaming reduces batch throughput time but increases the number of material handling moves.

The Daytona 500 racetrack in Florida has some of the best pit-crews in the world to service cars as they race for NASCAR. Each pit crew in NASCAR can contain up to 8 crew members, but only 5 are allowed in the pit at any time. In this scenario, the cars, as they stop, line up and have a crew member assigned. The crew members do not have the same service speed (see table below), but you should assume that all crew members can service a car in full regardless of title (meaning cars do not need to visit all crew members, they are serviced by 1 as they are assigned). Crew Member Pit Speed Jackman 4 cars per hour Tire Changer 6 cars per half hour Gasman 5 cars per 15 min Utility Man 7 cars per hour Tire Carrier 1 car per 10 min The pit-stop area (nicknamed Tartarus) is where each car is assigned a crew member and are serviced from right to left (meaning the last car is serviced first, then the 19th car and so on). 5a. How many cars can the entire crew serve in 1 hour? (5pts) [PartA] 5b. Identify the order of which the crew members should be placed in the pit (1st, 2nd, 3rd, 4th, 5th). (5pts) [PartB1st] , [PartB2nd] , [PartB3rd] , [PartB4th] , [PartB5th] 5c. Identify which crew member is the bottleneck for the whole pit. (3pts) [PartC]5d. Identify each range of cars the crew members will work when the pit-stop system reaches steady state (REMEMBER: Cars arrive right to left). Please show all work on scrap paper. (10pts) [PartD]

You are a proud engineer for Apple, on the team developing the newest iPhone! Your manufacturing plant is based out of Silicon Valley in California. The parts for each iPhone arrive from an upstream Poisson process with an arrival rate of 1 part every 5 minutes. All the parts that enter the system must go through a station which houses 2 prefabrication machines. A part, though, only requires to be processed by 1 of the 2 machines during prefab. The prefab time is exponentially distributed with the same mean for each of 8 minutes. If all the machines at the prefab station are busy, then the part will wait for the next available machine. [HINT: The machines do NOT break down and thus do not need to be repaired]. a. What is the probability that both machines are idle? Please round your answer to 3 decimal places (e.g. #.###). [PartA]  (4pts) b. What is the overall system utilization? [PartB] (2pts) c. What is the average number of parts waiting for prefab? [PartC] (2pts) d. A floor technician suggests that the system utilization rate should be lower (less than 30%) if the company wants to maintain the life of the machines and avoid machine failures. Do you think adding a third machine with the same processing rate will achieve that goal? Please show the new utilization rate to support your answer. Please express your answer to 3 decimal places and your asnwer (e.g., #.###, yes or #.###, no) and explain why on your scratch paper. [PartD] (2pts)

These Oscillatoria are cyanobacteria.  How do they get their food?

 A strand of DNA has the bases C A G C T A.  A new strand of DNA would have the bases: _____________________________.

How does this organism move?