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 47 millimeters high © 2011 jupiterimages corporation each cone of the hourglass has a height of 12 millimeters. the total height of the sand within the top portion of the hourglass is 47 millimeters. the radius of both the cylinder and cone is 4 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? a(6.4) b(62.4) c(8.5) d(56.0)