To make q the subject of the formula, we need to isolate q on one side of the equation. Starting with: t = √pq/r - r2 1. Add r^2 to both sides of the equation: t + r^2 = √pq/r 2. Square both sides of the equation to eliminate the radical: (t + r^2)^2 = pq/r 3. Multiply both sides of the equation by r: r(t + r^2)^2 = pq 4. Divide both sides of the equation by p: q = r(t + r^2)^2 / p Therefore, the answer is: q = rt2 / (p - r3)