# Question

Let the following relation schemas be given:

R = (A, B, C)

S = (D, E, F)

Let relations r(R) and s(S) be given. Give an expression in the tuple relational calculus that is equivalent to each of the following:

a. II A(τ)

b. σB =17 (τ)

c. τ × s

d. IIA, F (σC =D(τ × s))

R = (A, B, C)

S = (D, E, F)

Let relations r(R) and s(S) be given. Give an expression in the tuple relational calculus that is equivalent to each of the following:

a. II A(τ)

b. σB =17 (τ)

c. τ × s

d. IIA, F (σC =D(τ × s))

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