i- 1st blank- TestandSet(mutex).
2nd blank- mutext=0;
ii - no.
iii- say given procedure is not atomic. 1st execute process p1. After A1 p1 is preempted. 2nd process p2 now executes full code and enters critical section. P1 resumes and completes the code and enters critical section. So 2 processes are now in critical section.