a triangle has vertices A(2,3,7), B(0,-3,4) and C(5,2,-4).
a. determine the largest angle in the triangle
b. determine the area of triangle ABC
use the law of cosines to find two of the angles.
Then you can get the third, and the answer.
As for the area, it is a*b*sinC where a,b,c are the sides, and A,B,C are the angles (unrelated to the given points)