Final answer:
The question pertains to High School level Mathematics, focusing on geometry for area calculation and vector operations.
Step-by-step explanation:
The subject of this question is Mathematics, specifically geometry and the area calculation of geometric figures. The grade level of this question would be appropriate for High School as it involves the application of the coordinate geometry (finding the area of a triangle with given vertices) and vector operations (calculating resultant vectors and their magnitudes).
For example, to find the area of a triangle, one could use the determinant method or Heron's formula if the side lengths are known. For vectors operations such as vector sums and magnitudes, trigonometry and Pythagorean theorem are commonly used. These concepts are essential in the high school mathematics curriculum.