question_answer2) A toy is in the form of a cone of radius 3.5 cm mounted on a hemisphere of same radius on its circular face. The total height of the toy is 15.5 cm. Find the total surface area of the toy.
question_answer4) If the roots of the equation \[\left( {{a}^{2}}+{{b}^{2}} \right){{x}^{2}}-2(ac+bd)x+\left( {{c}^{2}}+{{d}^{2}} \right)=0\] are equal, prove that \[\frac{a}{c}=\frac{c}{d}\].
question_answer6) A takes 6 days less than B to do a work. If both A and B working together can do it in 4 days, how many days will B take to finish it?
question_answer7) From the top of a tower, 100 m high, a man observes two cars on the opposite sides of the tower and in same straight line with its base, with angles of depression \[30{}^\circ \] and \[45{}^\circ \]. Find the distance between the cars. [Take \[\sqrt{3}=1.732\]]
In the given figure, O is the centre of the circle with \[AC=24\text{ }cm,\,\,AB=7\text{ }cm\] and \[\angle BOD=90{}^\circ \]. Find the area of the shaded region.