Answer
(a) -6.62
(b)Magnitude of cross product is 5.55
Work Step by Step
(a)
Given:
A= 3.6 m
B=2.4 m
so
$\theta$=[ 30 + 90+(90-70)]
=$140^{\circ}$
(b)
The magnitude of cross product is $|A \times B|$ = $3.6 \times 2.4 \times sin(140)$= 5.55 , and the direction is perpendicular to the plan and is out of the paper .
