An hourglass consists of two sets of congruent composite figures on either end. each composite figure is made up of a cone and a cylinder, as shown below: hourglass with sand measuring 45 millimeters high © 2011 jupiterimages corporation each cone of the hourglass has a height of 15 millimeters. the total height of the sand within the top portion of the hourglass is 45 millimeters. the radius of both cylinder and cone is 6 millimeters. sand drips from the top of the hourglass to the bottom at a rate of 10π cubic millimeters per second. how many seconds will it take until all of the sand has dripped to the bottom of the hourglass?