Chapter 11 - Section 11.3 - The Tangent Ratio and Other Ratios - Exercises - Page 519: 43

47°

distance between tower and fire = d d= 200 ft $\times$ tan (90°-12°) d= 940.93 ft tan (90° - α ) $\times$ 1000 ft = d tan (90° -α ) = $\frac{940,93 ft}{1000 ft}$ tan (90°-α ) = 0.94 (90°-α) $\approx$ 43° α= 90° -43°$\approx$ 47°