A river 3 m deep and 40 m wide is flowing at the rate of 2 km per hour. How much water will fall into the sea in a minute?

Speed of river l = 2 Km/h = 2000 m/h, breadth b = 40 m and height h = 15 m
Volume of water fall into the sea in 1 hour = lbh = 2000 × 40 × 3 = 240000 m³
So, volume of water fall into the sea in 1 minute = 240000m³/60 = 4000 m³
Hence, in 1 minute, 4000 m³ will fall into the sea.