Four rational numbers p, q, r and s are such that q is the reciprocal of p and s is the reciprocal of r. The value of the expression (p + 1/q) ÷ (r + 1/8) / (8 + 1/r) ÷ (q + 1/p)is equal to: 1. 1 2. 0 3. pr 4. s/q