Consider the following relational schema.

Students(rollno: integer, sname: string)

Courses(courseno: integer, cname: string)

Registration(rollno: integer, courseno: integer, percent: real)

Which of the following queries are equivalent to this query in English?

"Find the distinct names of all students who score more than 90% in the course numbered 107"

(I) SELECT DISTINCT S.sname 
FROM Students as S, Registration as R 
WHERE R.rollno=S.rollno AND 
R.courseno=107 AND R.percent >90

(II) ∏_sname(σ_courseno = 107 ∧ percent > 90 (Registration ⋈ Students))

(III) { T | ∃S ∈ Students, ∃R ∈ Registration ( S.rollno=R.rollno ∧ R.courseno=107 ∧ R.percent > 90 ∧ T.sname=S.sname)}

(iv) { < S_N >| ∃S_R∃R_P ( < S_R, S_N > ∈ Students ∧ ∈ Registration ∧ R_P > 90)}

The smallest integer that can be represented by an $$8$$-bit number in $$2's$$ complement form is

Which one of the following expressions does NOT represent exclusive NOR of $$x$$ and $$y?$$

In the following truth table $$V=1$$ if and only if the input is valid.

What function does the truth table represent?