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Consider the following two pieces of code.   6 int Inser…

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 }

Suppose there are N workers concurrently running the followi…

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 }

Outline the common geological and biogeochemical events that…

Outline the common geological and biogeochemical events that were involved in triggering the Paleoproterozoic and the first Neoproterozoic global glaciations. What was one of the key consequences of both these events in terms of the Earth’s atmosphere? (10 pts)