3. The position vectors of the points \(A , B\) and \(C\) relative to an origin \(O\) are \(\mathbf { i } - 2 \mathbf { j } - 2 \mathbf { k } , 7 \mathbf { i } - 3 \mathbf { k }\) and \(4 \mathbf { i } + 4 \mathbf { j }\) respectively.
Find
- \(\overrightarrow { A C } \times \overrightarrow { B C }\),
- the area of triangle \(A B C\),
- an equation of the plane \(A B C\) in the form \(\mathbf { r } . \mathbf { n } = p\)