Final answer:
The question appears to involve a physics concept related to vector addition and the effects of crosswinds or currents on the path of an object, such as a boat, but the context provided is unclear.
Step-by-step explanation:
When a student asked about a rolling takeoff with crosswinds, it appears they may have provided erroneously related details about a boat's resultant velocity in a river. If the question were truly regarding rolling takeoffs in crosswinds, it would pertain to planes and the correct maneuvering techniques to maintain control during such conditions. However, the student might be conflating this with a physics problem involving vectors, where a boat has to compensate for a current to maintain a straight course across a river.
In such a case, the boat's pilot must steer into the current at the correct angle to achieve a resultant velocity that allows crossing straight. The example provided, wherein the resultant velocity of the boat is 10.0 m/s and it moves at a 26.6° angle, is a demonstration of vector addition, where the velocity of the boat and the velocity of the river current combine to create the resultant velocity.