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A 5′ 6″ female patient was admitted for exacerbation of her reactive airway disease. When the practitioner arrived to assess her and was found to be obtunded with slow shallow respirations. The following arterial blood gas was obtained on a 5L NC:   pH – 7.22 PaCO2 – 68 torr PaO2 – 78 torr HCO3 – 25 mEq/L BE – +1   The physician decided to intubate. What initial vent settings should the patient be placed on?

A/C volume control ventilation can be defined as [word1] and [word2] triggered, [word3] limited, and [word4] cycled. 

If the initial values for the semaphore is S = 0, A = 1, B = 0, how many times “1” will be printed?

Which of the following is NOT one of the properties that must be true in order for deadlock to occur?

If a thread holds a mutex lock then the thread prevents the OS from context switching to another thread.

Consider the following two pieces of code.   6 int Insert(list_t *L, int k) {7   node_t *n = malloc(8     sizeof(node_t));9   if (n == NULL) {10    perror(“malloc”);11    return -1;12  }13  new->key = k;14  pthread_mutex_lock(&L->lock);15  new->next = L->head;16  L->head = new;17  pthread_mutex_unlock(&L->lock);18  return 0; // success19 } 6 int Insert(list_t *L, int k) {7   pthread_mutex_lock(&L->lock);8   node_t *new = malloc(9    sizeof(node_t));10  if (new == NULL) {11    perror(“malloc”);12    pthread_mutex_unlock(13      &L->lock);14    return -1; // fail15  }16  new->key = k;17  new->next = L->head;18  L->head = new;19  pthread_mutex_unlock(&L->lock);20  return 0; // success21 }

If the initial values for the semaphore is S = 0, A = 0, B = 1, how many times “1” will be printed?

Failure to surround a critical section of code that accesses/changes a shared variable may result in what type of error?

Suppose there are N workers concurrently running the following worker function with arbitrary op_code parameters. As we can see, there are two different semaphores r0 and r1 declared in the following code.  They are respectively initialized with value R0 and R1. N, R0, and R1 are all positive integers. do_task_A() and do_task_B() functions won’t get stuck.    1 sem_t r0;   // Initialized with value R02 sem_t r1;   // Initialized with value R134 void *worker(void *op_code) {5 switch (*(int *)op_code) {6 case 0:7 sem_wait(&r0);8 sem_wait(&r1);910 do_task_A();1112 sem_post(&r1);13 sem_post(&r0);14 case 1:15 sem_wait​(&r1);16 sem_wait​(&r0);1718 do_task_B();1920 sem_post​(&r0);21 sem_post(&r1);22 }23 }

Lock Implementations, Hardware primitives, and Projects