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 employee_id |    date    | job_title_id | salary ————-+————+————–+——–           1 | 2020-01-01 |            1 |  50000           1 | 2020-06-01 |            2 |  45000           2 | 2020-01-01 |            1 |  50000           3 | 2020-01-01 |            1 |  50000           4 | 2020-01-01 |            2 |  45000           5 | 2020-01-01 |            2 |  45000(6 rows) Assume that the two following transactions are happening concurrently on the above table called employee_salary in Postgres. What is the output of “SELECT date FROM employee_salary WHERE employee_id = 2;” in (7), if each statement is performed in the order in the parenthesis?   BEGIN TRANSACTION ISOLATION LEVEL SERIALIZABLE; –(2)SELECT * FROM employee_salary; –(3)UPDATE  employee_salary SET date = ‘2020-03-01’ WHERE employee_id = 2; –(5)SELECT date FROM employee_salary WHERE employee_id = 2; –(7)COMMIT; –(8) BEGIN TRANSACTION ISOLATION LEVEL SERIALIZABLE; ; –(1)UPDATE employee_salary SET date = ‘2020-02-01’ WHERE employee_id = 2; –(4)COMMIT; –(6)

CREATE TABLE employee_salary (     employee_id NUMERIC,    date DATE,    job_title_id NUMERIC,    salary NUMERIC,    PRIMARY KEY (employee_id, date)); employee_id |    date    | job_title_id | salary ————-+————+————–+——–           1 | 2020-01-01 |            1 |  50000           1 | 2020-06-01 |            2 |  45000           2 | 2020-01-01 |            1 |  50000           3 | 2020-01-01 |            1 |  50000           4 | 2020-01-01 |            2 |  45000           5 | 2020-01-01 |            2 |  45000(6 rows) For the above table definition, what is the output of the last query, “SELECT COUNT(*) FROM employee_salary WHERE employee_id = 2; ” in the following transaction? BEGIN;INSERT INTO employee_salary VALUES (2, ‘2020-01-01’, 2,45000);COMMIT;SELECT COUNT(*) FROM employee_salary WHERE employee_id = 2;

 employee_id |    date    | job_title_id | salary ————-+————+————–+——–           1 | 2020-01-01 |            1 |  50000           1 | 2020-06-01 |            2 |  45000           2 | 2020-01-01 |            1 |  50000           3 | 2020-01-01 |            1 |  50000           4 | 2020-01-01 |            2 |  45000           5 | 2020-01-01 |            2 |  45000(6 rows) Assume that the two following transactions are happening concurrently on the above table called employee_salary in Postgres. What is the output of “SELECT date FROM employee_salary WHERE employee_id = 2;” in (7), if each statement is performed in the order in the parenthesis?   BEGIN TRANSACTION ISOLATION LEVEL SERIALIZABLE; –(2)SELECT * FROM employee_salary; –(3)UPDATE  employee_salary SET date = ‘2020-03-01’ WHERE employee_id = 2; –(5)SELECT date FROM employee_salary WHERE employee_id = 2; –(7)COMMIT; –(8) BEGIN TRANSACTION ISOLATION LEVEL SERIALIZABLE; ; –(1)UPDATE employee_salary SET date = ‘2020-02-01’ WHERE employee_id = 2; –(4)COMMIT; –(6)

There are two tellers at a bank. Customers come into the bank randomly starting at 8am. As customers enter, they will wait in a queue if the tellers are busy (following a first-come first-serve discipline). The manager of the bank decides to the operations for 60 minutes one morning (8:00 – 9:00am) and recorded the events that happened during that time period.  Just Finished Event Variables Statistical Accumulators [EntityID,Time,Event] Q(t) B(t) Ʃ TS ∫Q(t) ∫B(t) [-, 0, Init] – – – – – [1, 0, Arr] 0 1 – – – [2, 8, Arr] 0 2 – – 8 [1, 15, Dep] 0 1 15 –  14 [3, 20, Arr] 0 2 – – 5 [4, 30, Arr] 1 2 – – 20 [2, 32, Dep] 0 2 24 2 [a5] [5, 42, Arr] 1 2 – – [a6] [6, 54, Arr] 2 2 – 12 [a7] [3, 55, Dep] 1 2 [a1]   [a3] [a8] [4, 56, Dep] 0 2 [a2]   [a4] [a9] [7, 60, Arr] 1 2 – – 8 [-, 60, End] 0 2 – – [a10]

What is an appropriate expression to use in Simio to model the interarrival time from 2-5pm?

Average number of people waiting in queue is considered a counter statistic.

A local vegan burger food truck needs help understanding different aspects of their operations. The food truck is open from 12-7pm daily. Customers arrive to the food truck according to Poisson process at a rate of 30 customers per hour from 12-2pm, 15 customers per hour from 2-5pm, and 32 customers per hour 5-7pm.  The food truck serves three types of burgers. The most popular burger takes a minimum of 3 minutes, a maximum of 7 minutes, and can usually be completed in 5 minutes. Customers place an order with the cashier then travel 6 meters to pick up their food once it is ready. The time is takes to place an order is uniformly distributed with a minimum of 1 minute and maximum of 3 minutes. There is one cashier and two food servers/cooks. Once customers receive their food, they depart. A Simio model was developed to model customer flow between 5-7pm. The model was run with 10 replications for 2 hours and a 5-hour warm-up period.  What is an appropriate expression to use in Simio to model the interarrival time from 12-2pm? Note: Assume a time units of minutes.

Now assume the inter-arrival time is uniformly distributed, what would be the inter-arrival time of the first 3 customers using LCM. Assume   as above. Inter-arrival time ~ Uniform(a,b) Uniform PDF:

Average number of people waiting in queue is considered a counter statistic.

The financial statements of Burnaby Mountain Trading Company are shown below. EFG Corp.Income Statement 2018 Sales $7,000,000 Costs of Goods Sold 5,000,000————————- Gross Profit $2,000,000 Selling and Administrative Expenses 1,500,000————————- EBIT $500,000 Interest Expense 250,000————————– Income Before Tax $250,000 Taxes $100,000———————— Net Income $150,000   EFG Corp.Comparative Balance Sheets 2018 2017 Cash $90,000 $80,000 Accounts Receivable 810,000 800,000 Inventory 800,000 720,000 Total Current Assets ———————$1,700,000 ——————–$1,600,000 Fixed Assets 2,600,000——————— 2,400,000     ——————-  Total Assets $4,300,000 ___________________ $4,000,000 __________________ Accounts Payable $500,000 $400,000 Bank Loans 100,000———————- 100,000———————- Total Current Liabilities $600,000 $500,000 Long-term Bonds 400,000———————- 300,000———————- Total Liabilities $1,000,000 $800,000 Common Stock (20,000 shares) 500,000 500,000 Retained Earnings 2,800,000———————– 2,700,000———————- Total Equity $3,300,000———————– $3,200,000———————- Total Liabilities and Equity $4,300,000 $4,000,000 Note: The common shares are trading in the stock market for $27 each. Refer to the financial statements of EFG Corp. The firm’s times-interest earned ratio for 2018 is _________. Click on the arrow next to the file below. Next, create a new sheet in the Respondus LockDown Browser spreadsheet. You can use this blank spreadsheet to calculate the answer. Blank Spreadsheet.xlsx