3. Дана фигура, как показано на рисунке 1 . Найдите: А) тангенс угла между прямой \( A G \) и плоскостью \( A B C D \) В) тангенс угла между плоскостями \( F J I G \) и \( E H G F \).

6. ABCD is a quadrilateral, and AC and BD are its diagonals. Is \( \mathrm{AB}+\mathrm{BC}+\mathrm{CD}+\mathrm{DA}>\mathrm{AC}+\mathrm{BD} \) ? 7. ABCD is a quadrilateral and \( O \) is any point in its interior in the given figure Show that \( A B+B C+C D+D A<2(O A+O B+O C+O D) \).

111. The sum of the length, breadth and height of a cuboid is 38 cm and the length of its \( \vee \backslash \) diagonal is 22 cm . Find the surface area of the cuboid. Given : \( 1+b+h=38 \) and \( P^{2}+b^{2}+h^{2}=22^{2} \) To find : \( 2(l b+b h+h l) \)

102. The sides of right-angled triangle, containing \( \sqrt{ } 3 \) the right-angle, are \( 5 x \mathrm{~cm} \) and \( (3 x-1) \mathrm{cm} \). Calculate the length of the hypotenuse of the triangle, if its area is \( 60 \mathrm{~cm}^{2} \).

In the figure below, the chord \( E F \) subtends angle of \( 114^{\circ} \) at the centre \( O \). Calculate (a) the length of the chord \( E F \),

¿Cómo se calcula el área superficial de un cubo? Presenta la fórmula utilizada.