The horizontal distance between two stations $\mathrm{P}$ and $\mathrm{Q}$ is $100 \mathrm{~m}$. The vertical angles from $\mathrm{P}$ and $\mathrm{Q}$ to the top of a vertical tower at $\mathrm{T}$ are $3^{\circ}$ and $5^{\circ}$ above horizontal, respectively. The vertical angles from $\mathrm{P}$ and $\mathrm{Q}$ to the base of the tower are $0.1^{\circ}$ and $0.5^{\circ}$ below horizontal, respectively. Stations $\mathrm{P}$, Q and the tower are in the same vertical plane with $\mathrm{P}$ and $\mathrm{Q}$ being on the same side of $\mathrm{T}$. Neglecting earth's curvature and atmospheric refraction, the height (in $\mathrm{m}$ ) of the tower is
(A) 6.972
(B) 12.387
(C) 12.540
(D) 128.745
The horizontal distance between two stations $\mathrm{P}$ and $\mathrm{Q}$ is $100 \mathrm{~m}$. The vertical angles from $\mathrm{P}$ and $\mathrm{Q}$ to the top of a vertical tower at $\mathrm{T}$ are $3^{\circ}$ and $5^{\circ}$ above horizontal, respectively. The vertical angles from $\mathrm{P}$ and $\mathrm{Q}$ to the base of the tower are $0.1^{\circ}$ and $0.5^{\circ}$ below horizontal, respectively. Stations $\mathrm{P}$, Q and the tower are in the same vertical plane with $\mathrm{P}$ and $\mathrm{Q}$ being on the same side of $\mathrm{T}$. Neglecting earth's curvature and atmospheric refraction, the height (in $\mathrm{m}$ ) of the tower is
(A) 6.972
(B) 12.387
(C) 12.540
(D) 128.745