Montreal Mini-Covid Hospital is serving COVID-19 patients. The hospital is receiving 20 patients per hour for COVID test. At any given time, there are 5 patients waiting in line while the front desk is serving each patient in 3 minutes and directing 50% of patients to Dr. John and 50% of patients to Dr. Mary. At any given time, there are 15 patients in Dr. John's waiting room while he is serving each patient in 4 minutes and admitting 20% of his patients for treatment. Likewise, at any given time, there are 8 patients in Dr. Mary's waiting room while she is serving each patient in 5 minutes and admitting 15% of her patients for treatment. All details are presented in the process diagram below: Dr. John (GP) Service time - 4 min 20% Admit Waiting patients = 15 Patients 50% 809 20 / hour Front Desk Waiting Patients -5 Service time = 15% 3 min 50% Don't admit Dr. Mary (GP) Service time = 5 min 85% Waiting patients = 8 How long in minutes, does an admitted patient spend in the system on average, before the patient is asked to stay back for treatment (i.e. admit) in the hospital? 91.5 | 94.43 7.43 23.63 None of these answer choices

Katy is interested to understand the of herd immunity concept for Singapore's COVID-19 cases. She noted that 95% of adult population in Singapore is fully vaccinated by the end of October 2021. She want to compare difference of COVID-19 death cases in Singapore before Singapore achieve herd immunity and after Singapore achieve herd immunity. She collects the data of death cases in Singapore two weeks in the early of October 2021 (to represent before herd immunity) and two weeks in the end of No (Ctrl) -21 (to represent after herd immunity). Assume the variable is approximately normally distributed. The data are presented as below. Before herd immunity After herd immunity 121 109 118 76 117 105 132 53 40 68 55 45 41 24 78 74 64 93 103 68 88 63 47 37 48 45 40 29 a) Find 98% confidence interval of the difference in means.

A system has four independent and identical units in parallel. Each unit’s failure rate is 0.0005 failures/h. Calculate the system reliability, if at least two units must operate normally for the system success during a 100-h mission.

COVID-19 (novel corona virus) took the world by surprise in late 2019. By early 2020, nearly all countries worldwide were affected.Early reports from the US Centers for Disease Control and Prevention (CDC) estimated that approximately 3% of infected patients in the United States between the ages of 55 and 64 had died. This figure is known as the mortality rate of the virus for this age group. Suppose a sample of 1120 infected patients in the United States between the ages of 55 and 64 were randomly selected and 34 of the patients were known to have died. Use the p-value method to determine if the sample data support the conclusion that the mortality rate of patients between the ages of 55 and 64 is greater than 3%. Let α=0.01State the null and alternative hypothesis for this test. H0= H1= Determine the test statistic for the hypothesis test. Round the solution to two decimal places. = Determine the p-value for the hypothesis test. Round the solution to four decimal places. = Determine…