What is printed by the following ANSI C program?

 #include <stdio.h>
 int main(int argc, char *argv[]) {
    char a = 'P';
    char b = 'x';
    char c = (a & b) + '*';
    char d = (a | b) $$-$$ '$$-$$';
    char e = (a ^ b) + '+';
    printf("%c %c %c\n", c, d, e);
    return 0;
 }

ASCII encoding for relevant characters is given below :

Which one of the following regular expressions correctly represents the language of the finite automation given below?

Which of the following statements is/are TRUE?

Which of the following is/are undecidable?