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

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?

can someone me really understand this.