The Huka Falls on the Waikato River is one of New Zealand's most visited natural tourist attractions. On average, the river has a flow rate of about 300,000 L/s. At the gorge, the river narrows to 20m wide and 20m deep. What is the average speed of the river in the gorge? What is the average speed of the water in the river downstream when it widens to 50m and it depth increase to an average of 30m?