please i need help

Consider the below code of process P1 and P2, where S1 and S2 are two semaphores initialized to 0 and A10, A20, B10, B2() are four functions Semaphore S1 0 Semaphore S2 0 P2 P1 ( A10; Up(S2); Down(S1): B10 A20 Up(S1): Down(S2); B2) 1. What is the order of execution of the functions A1, A2, B1 and B2 that has been imposed by the use of semaphores? 2. Provide the code of a process Pi, that ensures the same kind of execution order for N processes, where Pi executes the functions Ai) and Bi()