help me solve these 3 ques. plzz:
Q. 4 A cylindrical tub of radius 12 cm contains water to a depth of 20 cm. A spha•ical iron ball is dropped into the tub and thus the level of the water is raised by 6.75 cm. What is the radius of the sphere?
(1) 9 cm (2) 3 cm (3) 12 cm (4) 18 cm
Q. 5 The height ofa cone is 30 cm. A small cone is cut off at the top by a plane parallel to its base. If its volume be 1/27 ofthe volume of the give cone, at which height above the base is the section cut ?
(1) 10 cm (2) 20 cm (3) 15 cm (4) 30 cm
Q.6 Water in a canal, 30 dm wide and 12 dm deep, is following with a velocity of 20 km per hour. How much area will it irrigate in 30 min, if 9 cm of standing water is desired ?
(1) 2 x 105 m2 (2) 4 x 105 m2 (3) 3 x 105 m2 (4) 7 x 105 m2
Refer the following links :
https://www.meritnation.com/ask-answer/question/a-cylindrical-tub-of-radius-20-cm-a-spherical-ball-is-drop/surface-areas-and-volumes/532238
https://www.meritnation.com/ask-answer/question/at-what-height-above-the-base-is-the-section/surface-areas-and-volumes/3660555
https://www.meritnation.com/ask-answer/question/water-in-a-canal-30-dm-wide-and-12-dm-deep-is-flowing-wi/math/3956565
https://www.meritnation.com/ask-answer/question/a-cylindrical-tub-of-radius-20-cm-a-spherical-ball-is-drop/surface-areas-and-volumes/532238
https://www.meritnation.com/ask-answer/question/at-what-height-above-the-base-is-the-section/surface-areas-and-volumes/3660555
https://www.meritnation.com/ask-answer/question/water-in-a-canal-30-dm-wide-and-12-dm-deep-is-flowing-wi/math/3956565