Final answer:
The River Kennet joins the Thames between the source and Henley. As a river flows downstream, it collects water from its tributaries, and its volume and flow increase. The Thames River, like other rivers, accumulates water from these tributaries and eventually reaches its mouth, where it enters a larger body of water.
Step-by-step explanation:
The River Kennet joins the Thames between the source and Henley.
In general, the Thames River flows from its source at Thames Head in Gloucestershire to its mouth at the North Sea. Along the way, it is joined by various tributaries, including the River Kennet. The River Kennet is a tributary of the Thames, meaning it flows into the Thames, increasing its volume and contributing to its overall flow.
As a river flows downstream, it collects water from its tributaries, and its volume and flow increase. The Thames River, like other rivers, accumulates water from these tributaries and eventually reaches its mouth, where it enters a larger body of water, such as a sea or an ocean.