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What is the field of quotients (or field of fractions) of an integral domain D?

In the following equation, which element is reduced? MnO2   +     +  HCl     –>     H2O     +      MnCl2      +        Cl2

In the following equation, which element is neither oxidized nor reduced? Al       +       Fe2O3      —>      Al2O3       +      Fe

In the following equation, which element is oxidized? Ba  +  O2   –>   BaO

Single answer: What would be the output at LINE C and LINE P when the program below executes? #include #include int value = 0;void *runner(void *param) {  value = 5;  printf(“%d”,value); /* LINE C */  pthread_exit(0);}int main(int argc, char *argv[]) {  pid_t pid;  pthread_t tid;  pthread_attr_t attr;  pthread_attr_init(&attr);  pthread create(&tid,&attr,runner,NULL);  pthread_join(tid,NULL);  printf(“%d”,value); /* LINE P */}

Multiple answers: Suppose the followings while executing a program execution on a 32bit x86 CPU computer system; %esp=0xffffcf8c %eip=0x804842b. The instruction at the memory address 0x804842b is call 0x80483dd. 0x8048430 is the next sequential instruction memory address after 0x804842b Select three statements that are *CORRECT* right after CPU fetch-and-executes the instruction “call 0x80483dd” at 0x804842b. 

Single answer: A semaphore variable can be used to order the execution of two treads T1 and T2. Select one *CORRECT* answer that correctly uses the semaphore variable “synch” to produce the output “BA” regardless of the order of scheduling on T1 and T2.    

Multiple answers: Select two answers that are *CORRECT* when the following program executes. You can reference pthread man page if you need. #include #include #include #define CORE 4#define MAX 8pthread_t thread[CORE];int mat_A[MAX][MAX], mat_B[MAX][MAX], sum[MAX][MAX];void* add(void* arg) {  int i, j;  int core = (int)arg; for (i = core * MAX / 4; i < (core + 1) * MAX / 4; i++)   for (j = 0; j < MAX; j++)      sum[i][j] = mat_A[i][j] + mat_B[i][j];  return NULL;}int main() {  int i, j, step = 0;                                                                  for (i = 0; i < MAX; i++)     for (j = 0; j < MAX; j++) {      mat_A[i][j] = rand() % 10;      mat_B[i][j] = rand() % 10;    }  for (i = 0; i < CORE; i++) {    pthread_create(&thread[i], NULL, &add                   (void*)step);    step++;  }  for (i = 0; i < CORE; i++)    pthread_join(thread[i], NULL);  return 0;}

Single answer: xchgl is a x86 machine instruction that reads a 32bit value from a memory location and sets a new value to the same memory location as a single atomic instruction. The following xchg is the mutual exclusion (mutex) implemented in xv6 os kernel using a xchgl x86 instruction. For your understanding, the machine effects are described in C.   static inline int xchg(volatile int *addr, int newval) { uint result; /* atomic read followed by update in a C version */ result = *addr; *addr = new; return result;} Select one that *CORRECTLY* implements a mutual lock to enter a critical section (mutual exclusion) using the xchg above.

According to your assignment, Sodium Polyacrylate (podcast), what was an interesting fact?