4. The length, breadth and height of a cuboid are in the ratio 19 : 11 : 13. If length is 30 cm more than height, then what is the volume (in cub.cm) of this cuboid?
5. 40 men took a dip in a pool 30 m long and 25 m broad. If the average water displaced by a man is 5 cub.m, then what will be the rise (in cm) in level of the pool?
6. Three solid spheres of radius 3 cm, 4 cm and 5 cm are melted and recasted into a solid sphere. What will be the percentage decrease in the surface area?
7. In triangle ABC, a line is drawn from the vertex A to a point D on BC. If BC = 9 cm and DC = 3 cm, then what is the ratio of the areas of triangle ABD and triangle ADC respectively?
9. In triangle PQR, A is the point of intersection of all the altitudes and B is the point of intersection of all the angle bisectors of the triangle. If ?PBR =105°, then what is the value of ?PAR (in degrees)?