Find the point P where the line x=1+t y=2t z=-3t intersects the plane x+y-z=-2
Find the distance from the point (-1,2,3) to the plane -1x+0y-2z=5
Plug this value into the parametric equation to find the point.
for part b write the plane is this form
and use the formula from this link
Point-Plane Distance -- from Wolfram MathWorld
I hope this helps.