When the boat moves on the surface of the water the resistance force of the environment F is directly proportional to the speed v (
![](https://st.testna5.ru/images/b6f/b6fe5223546c0910a70a68f33d8feebb.png)
, where
![](https://st.testna5.ru/images/c4b/c4bf2df7449b64c7256ab96817e073b9.png)
- coefficient of proportionality). At the moment of the engine shutdown the outboard motorboat is moving at a speed of 224 m/min., and 3 min. later it’s speed is equal to 112 m/min. 9 min. after the engine shutdown the outboard motorboat will be moving at a speed of ______ m/min.