A force F$$ acting at a point A$=(2\mathrm{.}9,1\mathrm{.}9,2\mathrm{.}2)$ m creates a moment M$=(0\mathrm{.}1$i$2\mathrm{.}1$j$+1\mathrm{.}1$k$)$kNm about the point B$=(3\mathrm{.}9,4\mathrm{.}4,2\mathrm{.}8)$ m$.$

Denote the line that is $($i$)$ parallel to the unit vector u$=(0\mathrm{.}4$i$+0\mathrm{.}6$j$+0\mathrm{.}6928$k$)$ and $($ii$)$ passing through point B by $.$

Answer the questions that follow.

a$)$

Let M$||$ denote the moment of F$$ about line $.$

$($This is per definition the projection of the moment of F$$ about B on $.)$

Calculate the magnitude of M$||.$

$$M$||=$

kNm

$1$ markUnanswered

b$)$

The sense of M$||$Answer for part b$)$

is the same as the sense of u$.$

does not exist, since M$||=0.$

is opposite to the sense of u$.$

$1$ markUnanswered

c$)$

Consider the corresponding perpendicular component M$$ of M$$ so that M$=$M$||+$M$.$

$($This means that M$||$ and M$$ are perpendicular to each other.$)$

Calculate the magnitude of M$.$

$$M$=$

kNm