int i = 0; void foo(void *) { int n = i; i = i + 1; printf("foo: %d ", n); } void boo(void *) { int n = i; i = i + 1; printf("boo: %d ", n); } int main(void) { tid_foo = create_thread(foo); tid_boo = create_thread(boo); // wait for threads to finish join_thread(tid_foo); join_thread(tid_boo); printf("main: %d ", i); return 0; } 4.1. What are the possible outputs of this program? 4.2. How could you avoid the race conditions? 4.3. What are the possible outputs, after you apply your solution to the prior