3. Point \( B \) is between points \( A \) and \( C \). The distances of \( A \) and \( C \) from point \( B \) are 1000 m and 2000 m , respectively. Measured from point \( B \), the angle of elevation of point \( C \) is \( 8^{\circ} \) 30 , while that of point \( A \) is \( \theta \). The difference in the elevations of \( A \) and \( C \) is 44.4 m , with \( C \) being lower than \( A \). Considering the effects of curvature and refraction, compute the value of \( \theta \).

When evaluating the expression \( \tan ^{-1}\left(-\frac{\sqrt{3}}{3}\right) \), the angle obtained is ...

Solve the equation for exact solutions over the interval \( [0,2 \pi) \) \( 2 \tan 3 x=2 \) Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The solution set is \( \left\{\frac{\pi}{12}, \frac{5 \pi}{12}, \frac{3 \pi}{4}, \frac{13 \pi}{12}, \frac{17 \pi}{12}, \frac{7 \pi}{4}\right\} \). (Type an exact answer, using \( \pi \) as needed. Type your answer in radians. Use integers or fractions for any numbers in the expression. Use a com B. The solution is the empty set.

(1) จงหาค่าของ \( 2 \sin 20^{\circ}+\cot 68^{\circ} \)

i) \( \frac{\tan \theta \cot \theta}{\sec \theta} \) equals: A \( \sin \theta \)

6 A plane flies on a true bearing of \( 280^{\circ} \mathrm{T} \) at \( 600 \mathrm{~km} / \mathrm{h} \) after taking off at 1300 hours. To the nearest kilometre, how far north of its starting position is it at 1530 hours?