The tension in cable $DE$ is $T=500N.$ For the force that acts at point $D,$ determine

$($a$)$ the scalar projection of T onto line FE $,$

$($b$)$ the vector expression for the projection of T onto line FE$,$

$($c$)$ the moment the force $T$ makes at $F,$ and

$($d$)$ the projection of the moment along the the line OF$.$