Answer
$\sqrt {265}$ units
Work Step by Step
Area of a given parallelogram is defined as:
$|{KL} ^{ \to} \times {KN}^{ \to}|$
Here, ${KL} ^{ \to} = \lt 1-1,3-2,6-3\gt= \lt 0,1,3\gt$
${KN} ^{ \to} = \lt 3-1,7-2,3-3 \gt= \lt 2,5,0 \gt$
${KL} ^{ \to} \times {KN}^{ \to}=|\lt 0,1,3 \gt \times \lt 2,5,0 \gt| = \lt -15,6,-2 \gt$
$|{PQ} ^{ \to} \times {PS}^{ \to}|=|\sqrt {(-15)^2+(6)^2+(-2)^2}| $
$= |\sqrt {225+36+4}|$
$=\sqrt {265}$ units