Considering the string statements below and assuming s1, s2 and s3 have been defined as strings (i.e., char [20]), answer questions a to c: (i) sl=strlen (s2); (ii) s3=s2*s1; (iii) printf("%s", s2); (iv) s2 [4] =s3[5]; (v) s2="AmIcorrect?"; a. Which statements are not syntactically correct? Why? b. Which statement(s) returns the size of a string? c. Which statement(s) copy a part of a string to another