A3. In a right triangle $A B C$ with a right angle at $C$, the altitude from vertex $C$ intersects side $A B$ at point $D$. What is the measure of angle $\angle B A C$ if $|C D|=\sqrt{12} \mathrm{~cm}$ and $|A D|=4 \mathrm{~cm}$?
(A) $\alpha \doteq 49,06^{\circ}$
(B) $\alpha \doteq 40,89^{\circ}$
(C) $\alpha \doteq 40,54^{\circ}$
(D) $\alpha \doteq 49,11^{\circ}$
(E) $\alpha \doteq 40,45^{\circ}$
A3. We use trigonometric functions in a right-angled triangle $\tan \alpha=\frac{v_{c}}{b_{1}}=\frac{\sqrt{12}}{4}=$ and calculate the angle $\alpha \doteq 40.89^{\circ}$. The correct answer is B.