Q. Runner A is initially 5km west of a flagpole and is running with a constant velocity of 7.5 km/h due east. Runner B is initially 3km east of the flagpole and is running with the constant velocity of 5.5km/h due west. How far are the runners from the flagpole while their paths cross?
Q. A unit of area, often used in measuring land areas, is the "hectare", defined as 104m2. An open-pit coal mine consumes 66hectares of land, down to a depth of 23m, each year. What volume of earth, in cubic kilometers, is removed in this time?