Question

I have this number that I just wanted to be sure how to do. They give me a Parallelepiped with corners lettered from A to H. Then the question is:

In a certain orthonormal reference, the coordinates of points A, B, D and E are respectively

A(0,0,2)
B(3,0,2)
D(0,4,2)
E(0,0,1)

Calculate the coordinates of point C in that same reference.

I determined that the coordinates for C are (3,4,2) but I have no idea how one goes to calculate that. I'm looking for a method to resolve this number.

Thank you