Subtract \( \frac28.8\pi \approx 9.17 \), so \( h^5/2 \approx 489.65 \) → \( h \approx (489.65)^2/5 \approx (489.65)^0.4 \approx 14.3 \) — but check: 12 to lower? Wait: negative sign means decreasing.